Airtel Wifi - Refund not received

I requested a airtel wifi installation on *nd July, they installed the wifi on the same day but it never worked. Airtel engineers came to check but there was some issue with the sim (provided by sales person), they suggested to change the sim but again the second sim wasn't working too. This happens till **th july. I then requested for the disconnection of wifi and it took them more than * days to even collect the device. They collect the device on **rd july. It took them a whole month to do this. I requested refund on the same day but no response. I can't reach out to them now since the sim is not working now. I can't call them, mailed them so many times but no response.


Now they are sending me the wifi bill, i haven't used their services for even a single day and they aren't refunding my money. I dont know whom to reach out now.