Airtel — Need online GST bill

Hello team,
This is how airtel started doing fraud..like WT[censored] I recharged my prepade number from airtel thanks app and i didn't received the GST bill i received the bill for previous month and for this month there is no option to download receipt. I called to CUSTOMER support and told me to go to airtel store...so what is this process all about we have to recharge online and for taking bill i need to go to store..such a ### company it is..
Highly unexpected.
If any ways to receive gst bill online kindly suggest