in the fuel select list,:
<select name="VehicleFuel" id="VehicleFuel">
<option value="">Please Choose</option>
<?php
do {
?>
<option value="<?php echo $row_WADADynListfuel['FuelName']?>"><?php echo $row_WADADynListfuel['FuelName']?></option>
you have set the value to use the fuel name, not the fuel ID