I agree with Vahid Ghafarpour, you can try the reauthorization he mentioned and check if that helps.
As far as I know, third-party email providers like Gmail, Yahoo, and iCloud require you to change certain settings on their website before you can add these accounts to Outlook. Please try logging into Gmail to check if POP and IMAP access are enabled.
Besides, here are the detailed steps to add Gmail, you can refer to: How to add Gmail account to Outlook using Imap? (extendoffice.com).
(Note: Since the web site is not hosted by Microsoft, the link may change without notice. Microsoft does not guarantee the accuracy of this information.)
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