Hello Emmanuel Balan1,
Welcome to the Microsoft Community!
When you encounter a Mac Mail prompt that you cannot verify your account name or password, we understand your frustration.
According to your description, I understand that in your computer, one account is normal while the other account has this problem, which seems to be caused by the problem of the account configuration file.
On the MacBook, there is no direct option to repair mail account profiles similar to the one in the Windows Control Panel. However, you can try the following steps to resolve email account issues:
For details,you can follow these documents:
- Remove your email account in Mail.
- Add your email account in Mail again. When adding the account, make sure that you choose the correct email service provider for your email address.
Disclaimer: Microsoft provides no assurances and/or warranties, implied or otherwise, and is not responsible for the information you receive from the third-party linked sites or any support related to technology.
Please note that this process may result in the loss of your local mail data, so it is recommended that you back up your mail data before performing this operation.
In addition, due to recent updates from Apple, there may be some differences in the Settings. If you cannot successfully complete the above operations, or the above troubleshooting steps do not work, you can contact the dedicated support personnel of Outlook for Mac support, please go to Help > Contact Support. Contact support within Outlook for Mac - Microsoft Support. They are more knowledgeable about Outlook for Mac issues and have more resources to investigate and fix issues.
I hope the above can point you in the right direction and wish you a smooth solution to the problem!
Best Regards ,
Morning | Microsoft Technical Support Community