As you are using a third-party email application, we will need to first figure out whether the issue comes from our mail server or from your side.
Please try to use our Webmail to send and receive email messages. If you are having trouble connecting to your email account from an external email application like Outlook but our Webmail is functioning as usual, you might have to go through the configuration settings again. Perhaps you have set something wrong somewhere.
But if our Webmail is not working as well, it means our servers may be encountering some issues. Please contact our support team immediately to get the problems sorted out.