Freeze you credit if you have the option.

Change the password on the account and turn on 2fa if it’s available.

If all your accounts use the same password, time to start changing those and use a password manager.

A password manager is probably your best defense against a future problem as it makes it very easy for each account to have unique passwords.

KeepassXC is a good free option. Bitwarden, ProtonPass have free, somewhat limited, options. Bitwarden is $10 a year the last time I checked.

Keep an eye out for sms and phone calls that are trying to scam, your bank, cc, and government accounts will not text or call you.