Reliance Smart Sector 122 Noida Uttar Pradesh - Cash not refunded

So I had a few essentials to purchase from Reliance Smart, Sector *** Noida, for which I used my DBS account for UPI payment. As I made the payment, from my account the amount was debited, but the cashier told me it hasn't been received and until it shows in their system he can't accept the fact that i made the payment. He told me to do it again, as the first payment would be refunded automatically, though I showed him the proof of debited amount, he wouldn't accept. So I made the *nd payment again, which was again debited from my account, still it wasn't showing in the system. The cashier along with other worker wouldn't give me the essentials and neither my debited amount. After almost **min of making them clear that two payments has been done, they still didn't help me out with the issue. I even spoke to their manager, but she too was of no help and kept on blaming my Bank account, saying that it will get refunded. At last with so much of frustrations and frantically trying to prove myself, I had to make the payment to the cashier's account then I could take the essentials. They assured me that my money would be refunded within *-* business days or at the most * days. So I went back to them after *days yet the money was not refunded. I spoke to the manager again, who blamed the IT team and told me that it's under process and by *days it will be refunded back to my account. It's been * days already and my amount has not been refunded. I'm a student and the amount of hassle I had to go through to get my money back just because thier system didn't show the amount debited, it has been very traumatizing for me to deal with the entire unnecessary situation.