jQuery preventing from submission : My html

  

    <p><select name="status" class="form-control" id="showThisItem">
                                  <option value="">
                                   Select Status
                                  </option>
                                  <option value="Paid">
                                    Paid
                                  </option>
                                   <option value="Unpaid">
                                    Unpaid
                                  </option>
                    </select></p>

               <td id="showHide">
                     <label>Due Date</label>
                     <input type="text" name="due_date" class="form-control" data-date-format="mm/dd/yy" id="datepicker" required="true"> 
               </td>

My jquery code

    <script>
     $('#showHide').hide(500);
      var showThis = $('#showThisItem');
      var select = this.value;
      showThis.change(function () {
        if ($(this).val() == 'Unpaid') {
            $('#showHide').show(500);
        }
        else {
          $('#showHide').hide(500);
        }
    });
    </script>

I have used this jquery code to hide and show a td element. When i will select "paid" the td will not show and when i will select Unpaid then the td will show. By default it will hide on page load.

However, if i select Unpaid then , i can submit the form and if i select Paid the submit button does not work.

Do not give me down vote for my question as i'm not so expert and I am new to this forum. Sorry for my bad English. Please give me a suggestion! Thank you for your time! 