Mumbai University — No receipt for the payment

I Darshana Mistry applied for Fyba on 10Dec 2021. I made the payment through gpay. The payment got stuck so I complained at airpay customer care service .they reverted that your payment will be refunded as transaction has failed.But I got confirmation of successful payment to the university of Mumbai on 13/12/2021.
Even after sending screenshot of transactions still the receipt is not being generated.
Above that, even after the successful payment receipt o the university of mumbai, airpay customer service centre says I should contact my bank .
Plz help me get my transaction receipt.Tired of mailing again and again I don't know why the customer care number is given when they are not able to resolve the matter.
I am attaching the screenshot of my payment receipts. Payment was done through my friends gpay .
Application form no 219818
Upi id[protected]
Amount is 3987.29
Kindly do the needful.