Use alternative website/apps -
SBI Unipay website, Jio Finance app, Airtel Thanks app and Canara Setu website.
Note -
Jio Finance app - Dnt use your saved credit card and debit card, always manually type your last credit card 4 digit and mobile number and always manually type debit card details and pay (If you face any error or otp page not open try this method). Also use latest version app.
SBI Unipay website - if any error then try without login and pay.