You can check whether your account is unable to send or receive mails, from within your cPanel.
Follow these steps –
1. Log in to cPanel.
2. Click on ‘Email accounts’ under Mail.
3. Create a new account firstname.lastname@example.org.(eg: email@example.com).
4. Log in to the Webmail of account by clicking ‘Webmail’ in ‘More’.
5. Enter the password for the account.
6. Select a service from the list.(Squirrel mail, Roundcube, Horde)
7. Try sending/receiving mails in the account.
If you are not able to send/receive mails through test account also, then the issue will be for all your accounts. Please contact us with the issue by log in to your client area and open a ticket to email: firstname.lastname@example.org
[Note: Try checking the above steps directly from your webmail. Please do not use the mail client for checking because it
can be the wrong configuration of the mail client which may also lead to non functioning of mail.]