UE not connecting to google play [ UE 4.7 P5]

Hello, I’m making a mobile Paper2D game (Blueprints only) and i’m trying to integrate my game with google play services. The thing is that my game doesn’t connect to google play; i have already set up the game services, uploaded the apk and linked it, filled out the form in the project settings in UE 4.7 but when the game starts it doesn’t connect to google play services as in say Tappy Chicken, also it won’t show leaderboards screen nor achievements screen. I have reseted my device to factory settings, tried to connect to the service using the blueprint node Connect to service (I recieve a 0 as an error code ), installing and uninstalling the app, uploading new apks, etc. Nothing works!. Someone told me to go to google settings and disconnect my app but it didn’t even appear listed.

I’d be very glad if you guys could help me with this as it’s stopping me from advancing my game’s development.

Note: I’m using Unreal engine 4.7 preview 5, the game worked when i had it on version 4.6, sadly i didn’t create a copy when upgrading.