Shree bazaar - Refund of online payment

I purchased groceries of Rs.*** on * june ****,from shree bazaar paradip,odisha,pin-******. And paid via google pay then the transaction gone under processing ,the again I paid via phone pe,that transaction also gone under processing.we took our groceries by exchanging cash after failure of two transactions, after that on * june,**** the transaction get successfully completed, On *th june,when we went to the respective shop ,then after checking that amount has been received, they denied to refund it , said it's against their policies,and said to mail to phone pe,we have also talked to phone pe customer care ,they said amount has been received to merchant account, how we can refund it,they should refund it.

Enclosure:- receipt of both transactions.

Kindly consider my problem and help.