How to appending data to FormData using jquery

 var formData = new FormData(this);

 formData.append('selected_socials', selectedSocials);

 <div class="modal-header">
                    <h4 class="modal-title mt-2"> Select social site and add cart</h4>
                </div>
                <div class="modal-body">                   
                <div class="card-body">
                <form method="post" id="addcarts" style="margin-left:-10px;" class="form-horizontal" enctype="multipart/form-data">
                                            @csrf   
                        <div class="row">
                            <div >
                            <div>
                                <input type="checkbox" id="selectAll" class="mr-2" onchange="selectAllSocial()">
                                <label for="selectAll"><b>Select All</b></label>
                            </div>
                                <div  id="facebooksocialContainer">
                                <input type="checkbox" class="socialCheckbox" id="face_priceCheckbox">           
                                    <span><b>Facebook: </b></span>
                                    <span id="facebooksocial"></span>
                                </div>
                                <div  id="twittersocialContainer">
                                <input type="checkbox" class="socialCheckbox" id="twitter_priceCheckbox">        
                                    <span><b>Twitter: </b></span>
                                    <span id="twittersocial"></span>
                                </div>
                                <div  id="youtubesocialContainer">
                                <input type="checkbox" class="socialCheckbox" id="youtube_priceCheckbox"> 
                                    <span><b>Youtube: </b></span>
                                    <span id="youtubesocial"></span>
                                </div>
                                <div  id="wordpresssocialContainer">
                                <input type="checkbox" class="socialCheckbox" id="wordpress_priceCheckbox"> 
                                    <span><b>Wordpress: </b></span>
                                    <span id="wordpresssocial"></span>
                                </div>
                                <div  id="tumblersocialContainer">
                                <input type="checkbox" class="socialCheckbox" id="tumblr_priceCheckbox"> 
                                    <span><b>Tumbler: </b></span>
                                    <span id="tumblersocial"></span>
                                </div>
                                <div id="instagramsocialContainer">
                                <input type="checkbox" class="socialCheckbox" id="instagram_priceCheckbox"> 
                                    <span><b>Instagram: </b></span>
                                    <span id="instagramsocial"></span>
                                </div>
                                <div id="quorasocialContainer">
                                <input type="checkbox" class="socialCheckbox" id="quora_priceCheckbox"> 
                                    <span><b>Quora: </b></span>
                                    <span id="quorasocial"></span>
                                </div>
                                <div id="pintrestsocialContainer">
                                <input type="checkbox" class="socialCheckbox" id="pintrest_priceCheckbox"> 
                                    <span><b>Pintrest: </b></span>
                                    <span id="pintrestsocial"></span>
                                </div>
                                <div id="redditsocialContainer">
                                <input type="checkbox" class="socialCheckbox" id="reddit_priceCheckbox"> 
                                    <span><b>Reddit: </b></span>
                                    <span id="redditsocial"></span>
                                </div>
                                <div  id="koosocialContainer">
                                <input type="checkbox" class="socialCheckbox" id="koo_priceCheckbox"> 
                                    <span><b>Koo: </b></span>
                                    <span id="koosocial"></span>
                                </div>
                                <div id="scoopitsocialContainer">
                                <input type="checkbox" class="socialCheckbox" id="scoopit_priceCheckbox"> 
                                    <span><b>Scoopit: </b></span>
                                    <span id="scoopitsocial"></span>
                                </div>
                                <div  id="slashdotsocialContainer">
                                <input type="checkbox" class="socialCheckbox" id="slashdot_priceCheckbox"> 
                                    <span><b>Slashdot: </b></span>
                                    <span id="slashdotsocial"></span>
                                </div>
                                <div  id="telegramsocialContainer">
                                <input type="checkbox" class="socialCheckbox" id="telegram_priceCheckbox"> 
                                    <span><b>Telegram: </b></span>
                                    <span id="telegramsocial"></span>
                                </div>
                                <div id="linkedsocialContainer">
                                <input type="checkbox" class="socialCheckbox" id="linkedin_priceCheckbox"> 
                                    <span><b>Linked In: </b></span>
                                    <span id="linkedsocial"></span>
                                </div>
                             <input type="hidden" value="{{ Auth::user()->id }}" name="admin_id" id="admin_id" />                   
                            <input type="hidden"  name="slug" id="slug" />
                            <input type="hidden" name="influencer_email"   id="influencer_email" />
                            <input type="hidden" value="{{ Auth::user()->email }}" name="admin_email" id="admin_email">
                            <input type="hidden" value="{{ Auth::user()->name }}" name="user_name">
                            <input type="hidden"  name="item"  id="item">
                            <input type="hidden" name="dataitem_id"  id="dataitem_id">
                            <button type="submit" name="action_button" id="action_button" class="btn btn-sm py-1 btn-primary me-2" value="Add">Add Cart</button>
                            </div>                            
                        </div>

    </form>

 $('#addcarts').on('submit', function(event) {
         event.preventDefault();   
         var selectedSocials = [];
    $('.socialCheckbox:checked').each(function () {
        selectedSocials.push($(this).attr('id').replace('Checkbox', ''));
    });

    // Log the selected socials to the console
    console.log("Selected Socials:", selectedSocials);
    if (selectedSocials.length === 0) {
        $('#social-modal').modal('show');
    }
    else
    {
      if ($('#action_button').val() == 'Add') {
        console.log('add action_button click ho rha ha');
        var formData = new FormData(this);

        // Include the selected socials in the FormData
        formData.append('selected_socials', selectedSocials);

        // Log the data to the console
        console.log("FormData:");
        for (var pair of formData.entries()) {
            console.log(pair[0] + ', ' + pair[1]);
        }
        $.ajax({
          url: "{{route('addcarts.store') }}",
          method: "POST",
          data: formData,
          contentType: false,
          cache: false,
          processData: false,
          dataType: "json",
          headers: {
            "Authorization": "Bearer " + localStorage.getItem('a_u_a_b_t')
          },
          beforeSend: function() {

          },

          success: function(data) {
           // Handle the response from the server
           console.log(data);
           var html = '';
           if (data.success) {         
            console.log('add success success click ho rha ha');
            $('#approve-modal').modal('show');
           }
           else 
           {

           }
         },
          error: function(xhr, status, error) {           
            console.log(error);
          }
        });
      };
    }
    })

$('.addToCartBtn').on('click', function() {
        event.preventDefault();
     console.log('add carting button click ho rha ha');    
       console.log('add button click ho rha ha');

        console.log('add carting button click ho rha ha');
        var admin_id = $('#admin_id').val();
            var slug = $('#slug').val();
            var influencer_email = $('#influencer_email').val();
            var admin_email = $('#admin_email').val();
            var user_name = $('[name="user_name"]').val();
            var item_id = $('#item').val();
            var dataitemId = $(this).data("item-id");
            console.log(item_id);
            var formData = new FormData();
            formData.append('admin_id', admin_id);
            formData.append('slug', slug);
            formData.append('influencer_email', influencer_email);
            formData.append('admin_email', admin_email);
            formData.append('user_name', user_name);
            formData.append('item_id', item_id);
            formData.append('dataitem_id', dataitemId);

            console.log("data aa gaya");
            console.log(selectedContainers.length);

            if ($('#selectedSocialContainersInput').val().split(',').length === 1) {
        const singleValue = $('#selectedSocialContainersInput').val();           
       $.ajax({
         url: "{{route('addcarts.store') }}",
         method: "POST",
         data: formData,
         contentType: false,
         cache: false,
         processData: false,
         dataType: 'json', // Specify the expected data type
         headers: {
        'X-CSRF-TOKEN': $('meta[name="csrf-token"]').attr('content') // Add CSRF token if needed
    },
         beforeSend: function() {          

         },
         success: function(data) {
           // Handle the response from the server
           console.log(data);
           var html = '';
           if (data.success) {         
            console.log('add success success click ho rha ha');
            $('#approve-modal').modal('show');
           }
           else 
           {

           }
         },
         error: function(xhr, status, error) {           
           console.log(error);
         }
       });   
    }