Hi, NeeNee Jac
Welcome to the Microsoft community.
Are you referring to your title? This title seems to point to a software installer provided by Avast. Have you installed any software from this company? If possible, could you provide some relevant screenshots of the issue and try logging into your Microsoft account using a mobile device to see if that works? Please also try following the steps in this article to see if you can unlock your account. If your account has been blocked due to suspicious activity, you may need to verify your security information to unblock it.
Unblock my Outlook.com account - Microsoft Support
If it still doesn't work, you can go to this website and fill out the form to seek further assistance.
Microsoft-Services Account Reset
Best regards
Tommy Jin | Microsoft Community Support Specialist