You may have a number of on line accounts and when account breaches occur you may not be informed that your account information has been compromised. Your account info could then be available on the internet, in a practice called a ‘pawned’ account.
There is a great site out there that collects data breaches and it can identify if your email is listed! You can check if your account/email here:
If your email is listed in an exploit then you should:
- not use that password anymore (it is listed publicly!)
- if possible try to change the password on the exploited site or close the account if you are not using it
For this reason it is good practice to use unique passwords for every account you have!