Reliance Smart Point Cheating

Hi community I genuinely need your suggestion/help about how I can take the refund of my double payment at the reliance smart point outlet it happened like this.

I first Paid via Paytm upi Money was deducted but the bill was not generated in their system cashier said no worries u will get the refund and try paying using another payment method hence believing him again I paid via Mobikwik wallent and its also successful and this time bill also generated but till date i have still not got my refund of payment that was successful from my end but bill not generated

on complaining it paytm they said its successful and order is delivered and reliance (even Mailed and called them many time) always told will get resolution in 7 days and after that register a new complaint.Almost 1 month passes but no Refund received Please Advice How To Proceed Forward

Thanking You