Do you mean the add in?
What is your coexistence mode?
It is up to your coexistence mode. If you are in Islands mode, you can choose either Skype meeting or Teams meeting.
If you are in Teams only mode, you can only choose Teams meeting.
After you upgrade to Teams only mode, it will wait several hours to take effect.
For more information about coexistence mode, please refer to this article: https://learn.microsoft.com/en-us/microsoftteams/teams-and-skypeforbusiness-coexistence-and-interoperability.
If the response is helpful, please click "Accept Answer" and upvote it.
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.