Mahanagar Telephone Nigam [MTNL] — refund my security deposit

Address:

110092

My name is alok kumar r/o h. No. A-330 flat no. 6 second floor budha marg, mandawali delhi-110092. Shadinagar, railway road, azadpur, delhi-110033. My tel no was 22472102, i had surrendered mtnl landline after paying all the outstanding amount on 16th march 2018 and i have been told that refund cheque/dd wil be sent to my address. But i didn't receive any dd from them. I request concerned department to look in to matter and send me the dd as soon as possible.