Thanks, Sergey. Error is gone, and my app is registering with backendless. However, I am not able to receive any push notifications. I have tried sending from the console, and from within the app. In both cases I can see the notification is scheduled, but no notification arrives.
I archived my app and installed it on my device. Push is now working in the production environment. It appears that using a universal certificate only works for the production environment. Is there any way to specify which environment to use with a universal cert?
Please make sure that you followed the instruction on configuring the push receival according to the doc page. In case the problem persists, create a dedicated topic for this new problem so that we could better track it and include thorough description of what you have already done with code samples you used.