Using Outlook for iOS for personal email and calendar management
Hey, i had the same problem but this seems to have worked (from Microsoft in-app support)
force close outlook (https://support.apple.com/en-us/HT201330)
then re-open outlook, go to the settings gear in bottom left hand corner. go to your account and click reset account. force close and repeat for each account you have.
appesrs to be working fine now in composing new emails, replies, and forwards.
This solution seemed unlikely at first, but it worked. I can type more than a few words at a time again. Thanks a lot. (Using the new Magic Keyboard.)
Worked for me too!!
thanks