I hope you are well. I think your MX records may not be updated properly to work for our webmail. The article below will help in in determining what they should be for your email plan with a link within the article if you are getting an "Pending Setup:MX error" on your email.
Follow these steps to resolve your issue.
In your cPanel dashboard, go to: Email > MX Entry > [select the associated domain] >
Check to see if "Local Mail Exchanger" or "Remote Mail Exchanger" is selected.
I needed "Remote Mail Exchanger" selected to make email delivery and receiving possible.
This may not be entirely related to your issue, however it would be a place to start. If you're unsure of what to do, definitely call in to support and see if they can assist you.