Emails failing since midnight last night

It looks as though emails have been failing since 12:02am cst. I am getting the following error:
Failed to validate emails. There was no endpoint listening at that could accept the message.

Hi Erik_Stave,

Could you please let us know, do you have a stable internet connection? Do you use a Proxy Server?

For the correct work of SQLBackupAndFTP, you have to have a stable internet connection. Internet is used for license validation. SQLBackupAndFTP communicates with our server through the API located at (port 433).

If you get any error messages, please send us a screenshot of the issue and a full text of the error message you get.

If there is anything else we can help you with, please let us know.

Thank you for using SQLBackupAndFTP.