My testing with google's ID product worked well. Now my apk is on Google's Beta and I'm using my own Product ID. Everything seems to be fine. I have Public Key in place and testers are mentioned in Google Play Console. However when I try in-app purchases it gives me "Something went wrong on our end. Please try again." message and in Log Viewer it says "Canceled Purchase". I've noticed that it also checked successfully "player can purchase goods", meaning it turned my boolean to true, but it ignored the rest of the code which mentioned which Product ID's can be purchased. It seems that the game or google don't know my Product IDs. I tried to make a new Product ID but it didn't help.
What should I look for or what to read to find the solution? I can't find anything useful in Stencyl's forum... nor in google actually.
