Hi
My name is Daniel. I am an Independent Advisor.
I'm wondering whether you are experiencing the same issue when using MS Teams online.
Please follow these steps below to isolate the issue:
1. Please go to your computer then open your chrome or edge browser as the only recommended browsers to access MS Teams online.
2. Please go to MS Teams online
https://teams.microsoft.com
3. Then try to log in.
4. Go check the chat history.
Are you experiencing the same issue when you are using MS Teams online from your computer?
If you're still unable to find on MS team online then please try to use the contextual search feature to find the chat, in some cases the chat can be hidden. If it's true once you found it via the search feature you need to unhide the chat.
See the demo video here on how to to use contextual search in MS Team:
https://www.youtube.com/watch?v=aQgJ2u0_Zf4
DISCLAIMER:
There's a link above from the non-Microsoft website. The page appears to be providing accurate, safe information. Watch out for ads on the site that may advertise products frequently classified as a PUP (Potentially Unwanted Products). Thoroughly research any product advertised on the site before you decide to download and install it.
Kind Regards