If you're repeatedly receiving a login alert on your Facebook account from an unknown device, browser, or location, don't ignore it. This could indicate a login from a new device or an attempt to access your account. In such a situation, it's important to immediately check your Facebook account security.

Carefully examine the Login Alert.
First, review the information displayed in the alert. This may include information such as the login time, device, and approximate location. If you didn't log in, open the Facebook app directly and verify your account instead of clicking on any suspicious links in the alert.

Change your Facebook password.
If you see an unfamiliar login, change your password immediately. Keep the new password strong and unique. Don't use a password you use on any other social media account or website.

Log out from unknown devices.
Go to Facebook's "Where You're Logged In" setting to see which devices your account is logged in to. If a device isn't recognized, log out of it. If necessary, you can log out of all devices and log in again only on your mobile device.

Enable Two-Factor Authentication
To increase account security, be sure to enable Two-Factor Authentication (2FA). This makes it difficult for someone else to access your account, even if they know your password.

Avoid suspicious links and apps.
Don't enter your Facebook password in an unknown email, message, or website. Also, check any third-party apps that have access to your Facebook account and remove them if they're no longer needed.

If you continue to receive Unknown Login Alerts after changing your password, double-check the activity in Facebook's Security and Login settings. If you continue to see suspicious activity, use Facebook's official Account Recovery and Security options.

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