Password autofill used to work perfectly for ICICI Bank. It used to work fine till a few days back but it’s likely that the bank has changed something at their end.
Please use the following link, if possible, to check the issue.
You can fill out an Auto-fill Failure Report for this site to let Bitwarden developers know about the problem.
The website design is intentionally designed to be hostile to users who rely on password managers, so there is no simple work-around for auto-filling this login form. I would suggest considering filing a complaint with the bank.