Have I Been Pwned?
Website – https://haveibeenpwned.com/
It will tell you whether or not your email has been found in any data leaks. If it has been, it doesn’t necessarily mean that your account has been compromised. Typically, the hackers will have gotten your email, username, and an encrypted version of your password. You should still change your password though.
https://www.justcol.com/united-airlines-telefono/