You receive an email to most likely one of the “generic” emails to your domain name… something like email@example.com or firstname.lastname@example.org.
The email states that your email box is beyond its capacity and that you must purchase additional space in order to continue to receive emails.
The email looks like this…
Many times this email will have a Microsoft Office 365 logo on it or some other “official looking” layouts that make you think that it might be a legitimate email.
Again, this is nothing more than a phishing attempt to try and get you to click on the link and enter wither payment information or password information so that the SCAMMER can get money or access to your account.
DO NOT CLICK ON THE LINK.