Pop-up "Zoho Mail Application is Disabled!"

Pop-up "Zoho Mail Application is Disabled!"

Hi there, I have received a pop-up saying "Zoho Mail Application is Disabled, please contact your administrator.!" I have successfully sent an email to the client and candidate and also have received confirmation - so everything is working great. I'm just a little unsure about the pop-up. Is there something I should be doing, but am not? Also if you can recommend any YouTube tutorials to watch on the basics of Zoho and the best I can get from it, that would be great. Thanks, Ria