Dr. B.r. Ambedkar University — 6th semester registration failure

Address:

Hyderabad, Jubilee hills, masthan nagar

I have paid my tution fee of 3rd year on 2021 August 8, i have wrote 5th semester in april 2022, now am unable to register for 6th semester, the website shows am not eligible for this semester, i don't know what was the reason behind it. I still have my proofs of receipts for tution fee of 3rd year & 5th semester...i have tried to contact the university regarding this through mails & calls but there is no response from the university..