If you suspect that someone is using your Gmail account without your authorization, we recommend that you change your password as soon as possible! With increasing cyber risks, you must take steps to protect your information and avoid the theft of your account. For maximum security, your new password should be a mix of letters and numbers, perhaps based on a phrase so that it's not easy to guess.
Most users have only one password for their Gmail account, and some users reuse their passwords across multiple accounts. We recommend you do not reuse password for multiple accounts. If you also use your Gmail password for other accounts, any other site that's compromised using this same password will expose you to your Gmail account being hacked. This is much more common than you might expect, so make sure to diversify your passwords.
Changing your password in Gmail is very simple. Sign into Gmail and click on Settings > Accounts and import. The click on Change password. After identifying yourself, enter the new password and confirm.
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