When Google detects unusual activity, your account can be blocked.
@gmail.com address - if your Gmail account has already been blocked by Google, please contact Google support directly as indicated on their dedicated support page.
G Suite account - as a G Suite admin, you can unblock your account up to 5 times per year. More information on the dedicated support page: Restore a suspended Gmail account
Mailmeteor does not have control over your email address. You have to ensure your activity respects Google's policies. Check our best practices guide to avoid being blocked by Google.
If you still need a helping hand on this, contact us. We'll be glad to help!