Indian Overseas Bank — Requesting for repayment of money

Dear sir/ madam

Name: subha
Amount paid online: 3200
Transaction date : 8/12/2020
Paid to alagappa university ( distance education fee)
I had paid my college fee using my debit card. After filling all the details they asked i had paid ( 3200) fee amount, it shows like " your payment is being processed. Then with in a minute it shows like sorry unable to process your payment. After that i had check my bank balance through gpay. Amount shows like debited but the transaction failed. So kindly refund the failed transaction.