Bharat Sanchar Nigam [BSNL] — Refund of deposit not received

I was having landline and broadband connection of bsnl. My landline number was[protected]. A/c no. [protected]. And customer id [protected]. I have submitted closure application for this connection on date 19/09/2019 to bopal exchange and also return the instrument on same date. I had also given cancelled bank account cheque in which my deposit refund is to be credited. I would like to draw your attention to the fact that even after completion of 10 months of my submitting closure application i have not received my deposit refund nor i am communicated when i will receive it. I request you to process my deposit refund and credit it, in by bank account. I have send email to [protected]@bsnl.co.in 3 times but have not received any response. Hoping for your kind co-operation.
Regards
Shaunak r delhiwala
Mobile no [protected]
Email : [protected]@yahoo.co.in