create some formualrs with php - problem with select-field

[DaMaxl]

Hi guys,
sorry...i'm a newbiiii and actually not that firm with php.
i create some formualrs using while loop.
the forms and input fields receives their names including a variable out of the database.

by submitting to another page almost all values are transmitted except the value of the select field.

I'm acutally using that ( it's just a shortcut ):

 

<form id='contact-form".$KitchConfigID."' name='contact-form".$KitchConfigID."' action='_pages/_kitchenconfig/adm_saveKitchConfig.php?Nav=".$NavHash."&kcid=".$KitchConfigID."' method='POST'>
  
  <div class='row'>

    <div class='col-sm-12'>
      <div class='md-form mb-0 form-sm'>
        <input value='".$KitchConfig."' type='text' id='configname".$KitchConfigID."' name='configname".$KitchConfigID ."' class='form-control'>
        <label for='configname".$KitchConfigID ."' class=''>Config Name:</label>
      </div>
    </div>

  </div>

  <div class='row'>
    <div class='col-sm-12'>
      <div class='md-form mb-0 form-sm'>
        <select id='designer_".$KitchConfigID."' name='designer_".$KitchConfigID."' class='mdb-select md-form' searchable='Search here..' onchange='changeInput(this.value, ".$SelField.");'>");
          $designersql = "SELECT * FROM `tbl_contacts` ORDER BY `FirstName`";
          $resultdesigner = $conn->query($designersql);

          if ($resultdesigner->num_rows > 0) {
          $resultdesigner->MoveFirst;
          echo("<option value='designer_".$KitchConfigID."'></option>");
          while($rowdesigner = $resultdesigner->fetch_assoc()) {
          $DesignerName = $rowdesigner["FirstName"]." ".$rowdesigner["LastName"];
          $DesignerID = $rowdesigner["ContactID"];
          if($rowdesigner["ContactID"]==$rowkitch["Designer"]){
          echo("<option value='".$DesignerID."' selected='selected'>".$DesignerName."</option>");
          }
          else {
          echo("<option value='".$DesignerID."'>".$DesignerName."</option>");
          }
          }
          }
          echo("</select>
        <input type='text' name='".$SelField."' value='' />
        <label for='designer_".$KitchConfigID."' class=''>Designer:</label>
      </div>
    </div>
  </div>
  
  
  <div class='md-form mb-0 float-right'>
    <button type='submit' class='btn btn-outline-danger waves-effect btn-sm float-right'>Save <i class='fas fa-magic ml-1'></i></button>
  </div>

For the Output i use:
 

    $upd_KitchConfigID = $_GET["kcid"];
    if(isset($_POST["configname$upd_KitchConfigID"]))
        {
           $upd_KitchConfig = $_POST["configname$upd_KitchConfigID"];
        }
        else
        {
            $upd_KitchConfig = 'NotSet';
            $ErrMsg = $ErrMsg . 'No KitchConfig, ';
        }
    
    if(isset($_POST["designer$upd_KitchConfigID"]))
        {
           $upd_KitchConfigDesigner = $_POST["designer_$upd_KitchConfigID"];
        }
        else
        {
            $upd_KitchConfigDesigner = 1;
            $ErrMsg = $ErrMsg . 'No Designer, ';
        }

echo("designer_$upd_KitchConfigID: ".$_POST["designer_$upd_KitchConfigID"]."<br><br>");

The value of ConfigName is well....BUT
for Designer i receive "Undefined index: designer..."

and i do not know why.
I'm shure it's a mistake by my stupid coding...but i can't find the error.

Maybe anybody of you guys can help me out?
thnx in advance!!!

BR,
Max

[requinix]

Underscores.