Mahanagar Telephone Nigam [MTNL] — non refund of security even unable to reach the concerned authority

Address:

110092

I have been port my dolphin connection no [protected] with other operator.
Still i am getting the bills while contact customer care they advise to contact sanchar haat. The sanchaar haat people internally don't know that who is responsible for this refund. While visited laxmi nagar sanchar haat they informed to send me to their landline refund branch again contact them then they told me to contact sanchaar haat idgah or cgo complex. Now i am unable to understand how my security will be refund. Mtnl dolphine people is not able to sorted out this issue.

My name account detail is given below:
Vishnu rastogi
Account no[protected]
Mobile no.[protected]
K-109 flat no 8 ganesh nagar extn ii
Shakarpur
Delhi-110092