Google blocked your account or considers your emails' links as suspicious. Why and what should you do?
My account has been blocked, what can I do now?
When Google detects unusual activity, your account can be blocked.
Solutions
@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.
Google Workspace or G Suite account: as a Google admin, you can unblock your account up to 5 times per year. More information on the dedicated support page: Restore a suspended Gmail account