Minecraft Bedrock (Android)

I have an Samsung Galaxy A3 2017 and i have found a game breaking buck for me (sometimes).
So when i start Minecraft it crashes, its goin black for a second and closes hiself, when im finally in a game in singleplayer/ Multiplayer (Server) i can play for like 15min or so then its going again black for a second and closes himself.
I reinstalled the Game Cleard Cache etc. But its closes it everyday it self