Mahanagar Telephone Nigam [MTNL] — refund of security deposit due to surrender of landline and bb

I had surrendered land line as well as of broad band of t. No.27347104 on 18/02/2020 vide book no.26 r. No.20. I had paid the outstanding mtnl bill of bill dated 7/02/2020 amounting to rs.890-00.in stead of refund again the bill generated amounting to rs.890-00. I had requested any shortcoming of material may be got adjusted from my security deposit lying with mtnl. Please resolve the issue at the earliest and after surrender the line is still active. Why should i pay for entire month. Please accommodate payment upto 18/02/2020 to my security deposit.
With regard
Ajit kumar singhal
[protected]@gmail.com
[protected]/[protected]