Well that's because of outdated api .
We will be releasing update of app and vibe course module to fix this in the beginning of next week .
That pay undefined is wallet feature .
refer this tip for wallet which uses android and ios's internal in app purchase option : https://www.youtube.com/watch?v=wv8hfZIivQs
Right now due to old api this is not working .but after update you will be seeing it working .