Check if your email, phone, or password is in a data breach.
Leaked email addresses can cause issues that range from minor annoyances to fully fledged attacks. Remember that in most cases all you need to login in is email and password, which makes your email half of the required information.
A leaked phone number can be used against you. An attacker who knows your phone number through a data breach maay be able to obtain a SIM card from you phone operator through social engineering techniques. This will likely allow them to access your accounts through standard recovery processes.
You can check if a password has been included in a known data breach. If a password is not found on Have I Been Pwned, that does not neccessarely mean that it is secure. Therefore, do not reuse the same password for multiple accounts and when a service you use suffers a data breach you should change your password and never reuse the old one included on the breach.