Hello Lilian,
Thanks for your reply and screenshots.
The last screenshot suggest that you need to try updating your account settings. Have you tried securing your account for two step verification? If you have tried, then you may need to use an App Password for your email setup on your phone. This way you will no longer get the error message about the updating of account credentials. Please go to update settings or visit settings in your Phone and remove then readd your account to see if issue persists.
Also, to make sure you remember, set up two step verification to your account, please make sure to add at least 3 security information. Then, follow the steps here: How to use two-step verification with your Microsoft account - Microsoft Support.
You may generate app password to use as method of authentication to your email account on a mailing application. Please follow the steps here: Using app passwords with apps that don't support two-step verification - Microsoft Support
If the change you mentioned is about the Auth for Exchange, this was implemented to secure the accounts in Exchange set up for verification and to lessen the authentication through password. In this case, we are not the right team to implement such change. Please send feedback to the team, scroll down and look for feedback option - Enable or disable SMTP AUTH in Exchange Online | Microsoft Learn.
Regards,
Kathy A.