Connect your Facebook account to QSID.
Attaching your account to QSID stops anyone from being able to log in to your account in any other way. Remember though, your QSID is only as secure as the email you sign up with!

Never share your account info with anyone.
Once your account security is compromised, it can be a difficult process to make it safe again and stop the other player from having access to it. Sharing accounts is against our Terms of Service and could get your accounts banned.
Never try to play other players' accounts.
If someone offers an account to you, they might actually be looking for a way to gain access to your accounts. You will also likely run into the same kinds of problems as if you shared your account.
Don’t share details about yourself or your account in Chat.
Sharing Personally Identifiable Information (PII) puts your privacy and your account security at risk. The questions will be innocent such as "What devices are you guys playing with?", "Anyone from the US here? What's your home town?" and so on. Your answers might then be used to seek you out in the real world or convince Support that your account doesn't actually belong to you but to the person asking you questions.
Don't try to recover your friend's account for them.
Attempting to recover other players’ accounts through Support is considered phishing. We have no way to verify whether your friend has asked for your help or not. Please ask your friend to contact Support themselves.