Google sign in signed apk not working

Question

Well all works till i generate the signed apk . I followed the entire process as told on the google developers page

1.I generated the google-services.json file with

Answer 1

I had the same problem. I think I found out that Google doesn't allow you to have one certification for both the debug and the release apk of your app. You need to choose to either get the certificate only for one of them. Please correct me if I am wrong.

What I did was to input the SHA1 fingerprint credentials for my release key and not my debug key on this link here

Afterwards, my released apk worked and not my debug key.