4th Gen iPad iOS 10.3.3 Connect to email from Office365

I'm the Office Admin at a very small office and have a lot of duties including 1st line defense for any IT issues which I normally fix. However, my co-worker gave me his iPad because he could no longer get email that was linked to our Office365 account. When I received his iPad his email was connected but he wasn't able to actually use it and we would get an error. I've since deleted the account to start over but when I try to connect to Exchange the furthest I can get is setting up an account that says 'Exchange Account This account may not be able to send or receive emails." If I ok that the mail slide button isn't active and won't let me make it active and ultimately the mailbox created says "Cannot Get Mail The connection to the server failed."

The iOS was no longer supported & the iPad could not be updated as it was too old. Gave employee a newer iPad and had no problems. Problem solved.