Madras University Distance Education Fee Payment — i paid the fees... it showing transaction success, amount debited from my bank account. but, when i click next it showing error.

Respected sir,
I am saibalaji, i paid tution fee for university of madras distance education through online payment of rs.7805.98 on 14/08/2020 22:37pm. It showed transaction success. But when i clicked next, it showing error. Then i tried to login again, it showing to me to pay the amount again. I dont know where the amount gone.
I am from poor family, they cant afford me to pay the fee again of rs 7805.98. I dont know what to do.. Please help me..
My transaction id:[protected]
Hereby i have attached transaction success and transaction id image for your reference.
Please help me as soon as possible... I dont what to do next.