If you are not able to see teams meetings in Outlook, it is likely that the teams add-in needs to be removed from the disabled add-in's list. To fix this issue follow the steps below.
1. Click on file.
2. Click on Options.
3. Click on Add-ins, then click on the drop-down arrow and select disabled items, then press GO.
Click on each row in the box, then select enable.
Close out, then re-open Outlook, and you should see the Teams add-in again.
If this does not fix the issue and you are still not able to see the Teams Meeting button in Outlook, then IT will need to perform a re-install of the Teams application to solve this issue.