Where you used ? Share some info. I will check.
Otp page is not open or something else ?
By d way BOI bank k khud k bahot se restriction ha like 2k se jada txn kabhi krne nhi dete ha, sometimes 10k se jada.
Hamesa bank denied jaise kuch error aa jata hai.
Isiliye mai hamesa private banks and private bank k RuPay cards use krta hu.
in jiomart also I am unable use my hdfc rupay card because of the similar kind of error posted by OP here.
Error-500, internal server error
from rfc 2068 hyper text protocol .. bla bla