Garmin explore collections

I have a problem.

When I create a collection in the Garmin Explore web app and add some waypoints and tracks to it, I cannot see that collection at all in the Garmin Explore Android app.

When I create a collection in the Garmin Explore Android app, it does not appear in the web app either.

I have tried reloading, signing out and back in, and syncing, but there is no change.

How can I sync web and android app?