Even after the app is published, when beta testers click to purchase a product, they see the message "This is a test order, you will not be charged"
I've removed the google groups from beta but still. What should be done? They cant buy normally
Was having the exact same issue until I realized this isn't about being in beta or not. For me it was about migrating from IAB v2 to v3. Specifically the accounts you have added in your 'Play Console > Settings > Account details > Gmail accounts with testing access'. I had accounts in there long before alpha/beta was possible. After removing them + 3 hours or so to propagate, the testing message stopped showing.
Might be documented in the v3 in-app billing somewhere but I didn't see it.