Hi Brenda9200
Thank you for posting your question here in Microsoft Community.
We recognize that you are able to access your account using a web browser without problems. Can you please verify if you've enabled Two-Step verification? Please refer to the steps below to check:
1. Sign in to your Microsoft account by going to http://account.live.com.
2. On the left side panel, click on Security info.
3. Click on “Turn off two-step verification” under Two-step verification.
Just in case you've enabled Two-Step Verification, you will need an app password to access your account when using mail apps. For more information, please visit the article below:
App passwords and two-step verification
Let us know if you need further assistance on this.
Thanks,