$(document).ready(function() {

    alert('Hi');
    if ($('#restDay2').val() == ' ') {
        $("#restDay2").find("option").prop("enabled", false);
        $("#restDay2").find("option").prop("enabled", false);
        if ($('#restDay1').val() != ' ') {
            currId = $('#restDay1 option:selected').attr('id');
            nextId = Number(currId) + 1;
            if (nextId > 7) {
                nextId = 1;
            }
            $('#restDay2 option').eq(0).prop('disabled', false);
            $('#restDay2 option').eq(nextId).prop('disabled', false);
        } else {
            $('#restDay2 ').val(" ");
        }

    }



});

Setting Validate Copy Format

<select id="restDay1" class="text_select" name="restDay1">
  <option value=" " id="0">
    - TransactionType -
  </option>
  <option value="Refund" id="1">
    Refund
  </option>
  <option value="Charge Back"  id="2">
    Charge Back
  </option>
</select>

<select id="restDay2" class="text_select" name="restDay2">
  <option value=" " id="0">
    - Payment Type -
  </option>
  <option value="SU" id="1">
    IPG1
  </option>
  <option value="MO" id="2">
    IPG2
  </option>
  <option value="TU"  id="3">
    WIPG1
  </option>
  <option value="WE" id="4">
    WIPG2
  </option>
  
</select>

Copy Format

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