Bank Of India — Amount Debited on incomplete Transaction

Address:

A-203, Hall 5, IIT Kanpur, UP, 208016

I was paying my academic fee at IIT Kanpur, Rs 15785 debited from my account but the transaction was not successful as the receipt stated that "Bank Declined Transaction" on 02/01/2022, 18:23. I haven't received that amount on my account yet, it has been more than 3 days. BOI Mobile is also not working it is, I am unable to even see my transaction history and mini bank statements.