Using Outlook for Android in business environments for email and scheduling
First, can you please provide your Outlook Android version? You can go to Settings > Help and Feedback > Scroll to bottom, you will see Outlook Android version.
Have you tried restarting you phone? If not, please restart and try launching Outlook Android again.
Try logging out of all the accounts, if you have another account, try logging in with another account. This will help narrow down if the issue is from the specific account.
Lastly, clear the browser's cache on your device. Then remove the app and re-install it.
Please try and let me know how it goes.
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