You are trying to login into Roundcube, and the following error appears:
In web hosting accounts using DirectAdmin, the error can be related to the suspension of the account associated with the email address you are trying to access.
If you have a web hosting account
Check if your web hosting account was not suspended for some reason. The account could have been suspended due to the lack of disk space. If that's the reason, performing an upgrade of your account will resolve the issue and unsuspend the account. Usually, you receive an email when this happens.
If you would like to check what's using that much space before performing an upgrade and prefer to check if it's possible to delete some data instead, you can temporarily ask us to unsuspend your account. However, take notice the account will be suspended automatically once again overnight in case it's still exceeding the allocated disk space.
If you have a reseller hosting account
Check if the account that is having this problem is not suspended for some reason. As a reseller, you can check the account status in the dashboard. Alternatively, you can see an exclamation mark in the list of accounts that can provide more information when passing the mouse over it.
As a reseller, you can log in as the user and check how the disk space is being used. You are also able to unsuspend the account even if it's exceeding the allocated disk space. However, take notice the account will be suspended automatically once again overnight in case it's still exceeding the allocated disk space.