Teams Issue - Spell Check not working within the Teams App
With the latest updates to Teams, there is an issue were the spell check feature stops working. It may still work, it may not, you may be able to fix it by clearing the Teams cache (see steps below), it may not and even if it does it looks like it stops working again a few hours or day after you clear it. Please note there is no current permanent fix for this issue at this time, but most likely Microsoft will release a patch in the near future.
Steps to Clear your Teams Cache can be found in the link below for Classic Teams, New Teams (which most of you are using now) and Teams for macOS.
Clear Teams cache - Microsoft Teams | Microsoft Learn