App testers on internal testing track can't use app actions

My testers are unable to test my app actions despite the following:

• testers are on the internal test email list in the play store console.
• testers have joined the App Actions Google group as recommended by the App Actions support team via email.

I myself am able to test them after joining the aforementioned Google group. Are there any other steps needed to grant the testers access?

It turned out the app name differed between the play store listing and the manifest. The testers were trying to use the name from the manifest, and that failed. But after they switched to using the play store listing name it started to work.