Google Play Service, cant sign in!

I follow this tutorial on youtube for googlplay services.

video tutorial:

the source link: https://github.com/playgameservices/play-games-plugin-for-unity


I have succesfully build it, after all the problems I encounter.
I already setup in the googleplay service the add test email account, and already publish there too.

but when Im trying to test my app, and sign it in to googleplay services, this thing promts

the application is incorrectly configured. Check the package name and signing certificate etc..




I really am struggling, right now, I have no Idea what should I do, Im sure the ID is the same in the app, and the package name too.

hopefully some one can help me. im stuck with it for days.

 

SHA1 fingerprint is true too?

 

Hi, yes I already resolve the problem here, what is missing in the tutorial, is the SHA1 certificate. ( this is my 1st time )

for everyone who wants to know how to generate the certificate that you will put on the googleplay service linked apps.
its quite confusing at the first time, but when you follow it step by step, then it will not have a problem.

WATCH THIS TO SEE HOW TO GENERATE CERTIFICATE THAT YOU WILL PUT IN ANDROID GOOGLEPLAY SERVICES AND UNITY:

this is my first time to upload and use google service ( achievements leaderboard). and Im very happy thats its working now.

 

To get SHA1, I'm creating an eclipse android project with my package name and signing with my keystore. You can get from ui.