Airtel — unable to recharge online airtel prepaid number after porting from postpaid

Hi,

I have ported my postpaid airtel to prepaid plan in feb 2020.
I have done the frc from shop as suggested. But even after that i am not able to make any online recharge for my number.
Trying to contact airtel via 100 different ways from march.
Its been 4months and i am struggling to get this rectified.
Please help.

Thanks in advance,
User