can i update choice fillings when once i filled and locked

According to the JoSAA (Joint Seat Allocation Authority) rules, once you've locked your choices, you can't modify them. However, there are a few exceptions:

1. *Before the final locking*: If you've filled and saved your choices but haven't locked them yet, you can still modify them.

2. *During the "Correction Window"*: JoSAA usually opens a correction window for a short period after the choice-filling deadline. During this time, you can make changes to your choices.

3. *By contacting JoSAA helpdesk*: In exceptional cases, you can reach out to the JoSAA helpdesk and request changes to your choices. However, this is only possible if you have a genuine reason and the authorities approve your request.

Remember, it's essential to carefully review and double-check your choices before locking them to avoid any issues.