Document ID is not capturing in form using dropzone library

I am using form and dropzone library to upload document and I was doing testing whether my document ID is capturing or not. Its not capturing and when I check and see the issue is my form dropzone library is preventing it and I am not sure why. I will appreciate any help to identify the issue

This is my code

var tblCandidateDocumentList = $('#tblCandidateDocumentList').DataTable({
        ajax: {
            "url": "action/fn_espdb_getData.php?mod=candidateDocumentList",
            "dataSrc": "candidateDocumentList"
        },
        columns: [
            { data: null },
            {data: null},
            { data: 'document_type_name' },
            {
              data: null,
                render: function (data, type, row) {
                    return `
                      <div class="col-12">
                        <div class="card">
                          <div class="card-body">
                            <form action="/upload" class="dropzone dropZoneCandidate needsclick" data-doc-id="${row.document_id}" id="dropzone-multi-${row.document_id}">
                              <input type="hidden" id="documentTypeID" name="documentTypeID" value="${row.document_id}" class="form-control" readonly>
                              <div class="dz-message needsclick">
                                Drop files here or click to upload
                              </div>
                              <div class="fallback">
                               <input id="file_${row.document_id}" name="file_${row.document_id}" type="file" multiple/>
                              </div>
                            </form>
                          </div>
                        </div>
                      </div> 
                  `;
                }
            },
        ],
        columnDefs: [
          {
            // For Checkboxes
            targets: 0,
            searchable: false,
            orderable: false,
            render: function () {
              return '<input type="checkbox" class="dt-checkboxes form-check-input">';
            },
            checkboxes: {
              selectRow: true,
              selectAllRender: '<input type="checkbox" class="form-check-input">'
            }
          },
        ],
        order: [[1, 'desc']],
        dom: '<"row"<"col-sm-12 col-md-6"l><"col-sm-12 col-md-6 d-flex justify-content-center justify-content-md-end mt-n6 mt-md-0"f>><"table-responsive"t><"row"<"col-sm-12 col-md-6"i><"col-sm-12 col-md-6"p>>',
        language: {
            paginate: {
                next: '<i class="bx bx-chevron-right bx-18px"></i>',
                previous: '<i class="bx bx-chevron-left bx-18px"></i>'
            }
        },
        select: {
            style: 'multi'
        }
    });

This is my backend code

case “addCandidateDetails”:

    // Collect form data
    $candidateID = $_POST['candidateID'] > 0 ? $_POST['candidateID'] : NULL;
    $candidateName = $_POST['candidateName'] == "" ? NULL : $_POST['candidateName'];
    $candidateNationality = $_POST['candidateNationality'] == "" ? NULL : $_POST['candidateNationality'];
    $candidateGender = $_POST['candidateGender'] == "" ? NULL : $_POST['candidateGender'];
    $candidateMaritalStatus = $_POST['candidateMaritalStatus'] == "" ? NULL : $_POST['candidateMaritalStatus'];
    $candidateDOB = $_POST['candidateDOB'] == "" ? NULL : $_POST['candidateDOB'];
    $candidateAge = $_POST['candidateAge'] == "" ? NULL : $_POST['candidateAge'];
    $candidateEmail = $_POST['candidateEmail'] == "" ? NULL : $_POST['candidateEmail'];
    $candidateCompany = $_POST['candidateCompany'] == "" ? NULL : $_POST['candidateCompany'];
    $candidatePassportNo = $_POST['candidatePassportNo'] == "" ? NULL : $_POST['candidatePassportNo'];
    $candidatePassportIssueDate = $_POST['candidatePassportIssueDate'] == "" ? NULL : $_POST['candidatePassportIssueDate'];
    $candidatePassportExpiryDate = $_POST['candidatePassportExpiryDate'] == "" ? NULL : $_POST['candidatePassportExpiryDate'];
    $candidatePlaceOfIssue = $_POST['candidatePlaceOfIssue'] == "" ? NULL : $_POST['candidatePlaceOfIssue'];
    $inMalaysia = $_POST['inMalaysia'] == "" ? NULL : $_POST['inMalaysia'];
    $visaCollectionCenter = $_POST['visaCollectionCenter'] == "" ? NULL : $_POST['visaCollectionCenter'];
    $candidatePermitType = $_POST['candidatePermitType'] == "" ? NULL : $_POST['candidatePermitType'];
    
    // Additional data for tbl_candidate_documents
    $documentTypeID = $_POST['documentTypeID'] == "" ? NULL : $_POST['documentTypeID'];

    // File upload handling
    $uploadDirectory = '/uploads/candidate_files/';
    $uploadedFilePath = NULL;

    echo "Candidate Name : " . $candidateName . "<br>";
    echo "candidate Nationality : " . $candidateNationality . "<br>";
    echo "Candidate Permit Type : " . $candidatePermitType . "<br>";
    echo "Candidate Document ID : " . $documentTypeID . "<br>";
    exit();



    
    
    if (isset($_FILES['candidateFile']) && $_FILES['candidateFile']['error'] == UPLOAD_ERR_OK) {
        $fileTmpPath = $_FILES['candidateFile']['tmp_name'];
        $fileName = $_FILES['candidateFile']['name'];
        $fileExtension = pathinfo($fileName, PATHINFO_EXTENSION);

        // Sanitize candidate name and passport number for the filename
        $sanitizedCandidateName = preg_replace("/[^a-zA-Z0-9]/", "_", $candidateName);
        $sanitizedPassportNo = preg_replace("/[^a-zA-Z0-9]/", "_", $candidatePassportNo);

        // Construct the new file name
        $newFileName = "{$sanitizedCandidateName}_{$sanitizedPassportNo}_Document.{$fileExtension}";
        $uploadedFilePath = $uploadDirectory . $newFileName;

        // Move file to the destination
        if (move_uploaded_file($fileTmpPath, $_SERVER['DOCUMENT_ROOT'] . $uploadedFilePath)) {
            // Insert file details into tbl_candidate_documents
            DB::insert('tbl_candidate_documents', [
                'candidate_id' => $candidateID,
                'document_type_id' => $documentTypeID,
                'permit_id' => $candidatePermitType,
                'document_name' => $newFileName,
                'document_path' => $uploadedFilePath,
                'status' => 1,
                'entry_user' => $username,
                'entry_date' => DB::sqlEval('NOW()')
            ]);
        } else {
            die('Error uploading file.');
        }
    }

    // Insert candidate details into tbl_candidate
    DB::insert('tbl_candidate', [
        'candidate_id' => $candidateID,
        'candidate_name' => $candidateName,
        'candidate_nationality' => $candidateNationality,
        'candidate_gender' => $candidateGender,
        'candidate_dob' => $candidateDOB,
        'candidate_age' => $candidateAge,
        'candidate_email' => $candidateEmail,
        'candidate_customer' => $candidateCompany,
        'candidate_passport_no' => $candidatePassportNo,
        'passport_issue_date' => $candidatePassportIssueDate,
        'passport_expiry_date' => $candidatePassportExpiryDate,
        'candidate_issue_place' => $candidatePlaceOfIssue,
        'candidate_is_in_malaysia' => $inMalaysia,
        'candidate_visa_collection_center' => $visaCollectionCenter,
        'candidate_permit_type_id' => $candidatePermitType,
        'status' => 1,
        'entry_user' => $username,
        'entry_date' => DB::sqlEval('NOW()')
    ]);

    break;