Hi niroshan, before you can delete MDN, you need to delete the mns funciotn on it (it's the function that permit the click and dial), the command chain should be something like this:
KSFKC:DIR=7402,KEY=14,FCN=MDN;
KSMDE:DIR=7402,MDN=7430;
After this command the keys it will be free, so you can...