No styling that seem to affect the Modal

modal.php

<div class="modal fade" id="newChannel" tabindex="-1" role="dialog" aria-labelledby="exampleModalCenterTitle" aria-hidden="true">
          <div class="modal-dialog modal-dialog-centered rounded" role="document">
            <div class="modal-content border-0 rounded">
              <div class="modal-header text-center">
                <h4 class="modal-title">Add Channel</h4>
              </div>
              <div class="modal-body modal-body-diff rounded p-5 ">
                <div class="add-new-channel">
                    <form action="/channel/add" method="POST" class="my-3" >
                      @csrf
                        <div>
                          <select name="channel" class="custom-select colored-form-control custom-select-lg mb-4" placeholder="" id="channel-name">
                            <option selected value="">Pick a channel</option>
                             @isset($channels)
                             @foreach ($channels as $channel)
                              <option  value="{{$channel}}"> {{$channel->name}}</option>
                              @endforeach
                              @endisset
                          </select>
                        </div>
                         <div class="inputWithIcon">
                         <!-- style="font-size:15px;"  -->
                            <input type="text" class="show-read-only-api form-control form-control-lg mt-0" disabled placeholder="Channel Api">
                        </div>
                        <div id="instructions">

                        </div>
                        <div class="inputWithIcon">
                            <input type="text" required="required" name="hotel_id" placeholder="Hotel ID" class="form-control form-control-lg mt-0 colored-form-control">
                            <i class="fa fa-home fa-fw text-light o-5 fa-lg mt-2"></i>
                        </div>
                        <div class="inputWithIcon form-group">
                            <input type="password" required="required" name="password" placeholder="Password" class="form-control form-control-lg mb-1 colored-form-control">
                            <i class="fas fa-eye fa-fw text-light o-5 fa-lg mt-2"></i>
                            <small id="emailHelp" class="form-text text-white mt-2 pt-0 ml-5">No password? <span class="text-underline cursor-pointer">Get one here</span></small>
                        </div>



                        <button type="submit" class="btn btn-primary btn-submit btn-lg"><span>Add Channel</span></button>
                        {{-- <a class="nav-link"></a> --}}
                    </form>
                </div>
              </div>
            </div>
          </div>
        </div>