if you found the keystore that you created, you have to go to
google play developer console ==>
game services ==>
game details (scroll toward bottom) ==>
find the link that says “This game is linked to the API console project called 'Your Game” ==>
credentials (on the left side under library) ==>
now click on your game ==>
now you should see this “keytool -exportcert -alias YOURALIAS -keystore YOURKEYSTORE -list -v” ==>
paste the keystore you generated under this