Using the answers before, I used this as a link to understand and correct mine and make a much easier step-by-step procedure for how I fixed mine.
At the windows command prompt.
Go to the java bin directory.
C: \ Program Files \ Java \ jdk1.8.0_111 \ bin>
and type ff. Team
keytool -list -v -keystore "%USERPROFILE%\.android\debug.keystore" -alias androiddebugkey -storepass android -keypass android
then run ff. the code
keytool -list -keystore "%USERPROFILE%\.android\debug.keystore" -alias androiddebugkey
when prompted for a password, enter "android" (without double quotes)
received SHA1 key from the above code. Copy it and paste it into your Google cloud console here

On google cloud console webpage do it
on the tab on the left, find and click "API and Services"
then on the new page, on the left tab, find and click "Credentials"
now copy the key paste that you copied from the Windows command prompt into the text box below "Subscriber certificate fingerprint"
make sure the application ID on your application and the Google Cloud Console match.

Joshua cariño
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