Google Leaderboard not support?

Hi
We are working on one android base game. It’s mostly like a subway surfer where the main character has to collect some items according to what the score will generate. Now our game is in its final stage. The scores are generating, high scores also generate our game save in internal storage. Now we want to add google leaderboard in this game. all the necessary things are done by us on google console (ie oAuth ID, Leaderboard name, App ID). We incorporate the leaderboard Name & Key in unreal Engine project settings. When we generate the build and install it in mobile the Google Play store logging is done. We gave a leaderboard button on home screen when we press the leaderboard button before start to play the leaderboard is showing. When we go back to our game and start to play once game over we try to access the leaderboard with that button it won’t display leaderboard and also the game is closed.
Can anyone pls help me out regarding the blueprint or any other issue regarding this.