If access to your bank account, Facebook or email became compromised and ill-intentioned people are able to access them, here is what you should do.
This is the first thing you should do to protect your data. You should do this right away, before a criminal has had the chance to access your data and change your password themselves. You should do this on a computer you trust.
If you are unable to log in to your account immediately to change your password, call your administrator so they can block your account.
Some webmail systems enable you to view all attempts to access your account and detect whether any suspicious attempts have taken place.
It is not advisable to use the same password for more than one account. If necessary, you should change the log-in details for all your accounts, without forgetting anything.
They may be able to take practical steps to protect other users, in the event of a large-scale attack.
You should immediately notify your account administrator so they can block access to the account in question. They will usually be able to reset it with a new password.
If any information grants access to other accounts, take steps to protect them (points 1 and 2).
If your mailbox has been compromised, check whether any confidential information was stored in it. If so, take suitable measures to protect this information. If necessary, warn any contacts who exchange confidential information with you. Also look at the password reminder functions for all the online services you use which refer to your email address to regenerate a password. Make sure the attacker hasn’t changed other accounts that you access through the compromised account.