How to set up Mail account on Mac successfully?

Hello, I am trying to set up my mail account on my Mac. It stopped working when I registered my new iPhone. I have tried deleting the account and reloading it, but I still get the message saying it's unable to verify the account. I know my login credentials are not the problem, as Mail is working on both my new iPhone and my iPad. And I can even send messages from the account on my Mac. It just won't receive them.

Can anyone advise? I tried a hint suggested on a much earlier thread about tabbing to the next field after entering the password, but that didn't work.

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