problems with outlook password

[jerryham2@att.net]

Good morning


I'm new on this forum, so I apologize if I do something incorrectly. I have two email accounts on my 2016 version of Outlook. I am using windows 10 operating system. The email account I use most for my business stopped sending and receiving all emails. The error message that I got said that the server could not log onto the email address and that I should check my password. I have not changed that password for years. I would reenter the correct password, and got the same results.

Someone told me to delete the account from Outlook and add it back in as a new account. When I did that it will not let me set up the account since it asks for a password. When I enter my password it tells me it is wrong, but there is nowhere at that point to change the password. The email address that I have is an @att.net domain which is accessed through Yahoo mail. I can access my emails through yahoo mail just fine as well as on my IPhone. Only in Outlook am I having this issue. the other email account which is a gmail.com domain seems to be working fine. How do I get this address into Outlook even just to change the password?
Any help would be appreciated.