National Board Of Examination — 1st year fee refund from round 1 after upgrading in round 2.

I was alloted a dnb OBG seat in all india quota 1st round neet pg counselling 2021 conducted by mcc. I submitted 1st year fee for DNB and reported to the alloted seat.
I got upgraded to ms surgery seat in 2nd round of counselling so I got relieved from that DNB seat and took admission for MS seat. I want refund of my 1st year DNB fee
For that I have mailed at [protected]@natboard.edu.in multiple times with copy of admission letter and fee submission receipt attached with it
But no I have not got any response
Kindly do the refund of my fee as soon as possible.

Please let me know the correct process for refund initiaion at least. That will be very helpful.