Power app added to teams site is not pulling gallery into Teams. Power app will work online.

Power app added to teams site is not pulling gallery into Teams. Power app will work online.
Hi @hpb,
Do you want to create an app with a Gallery in Teams?
Could you please provide more details about your app? What does it mean to pull the gallery into Teams? Nothing is display in your gallery, right?
I have made a test but it seems that works fine on my side.
1. Create a new app.
2. You can select the Gallery you want in the Insert pane on the left, and then connect the data source you need.
3. Once you have created your application, you can save your changes and preview the application.
4. Select Publish to Teams to publish the app so others in your team can use the app, and add the app to Teams channel.
6. The App appears in Teams.
7. In addition, it may also be affected by the control, you can also try to enable the classic controls.
Best Regards,
Charlie Choi