In-game store close

So every time i go into the in-game store to collect the free pack. When i back out to the home screen it automatically closes the game and restarts it. This is happening everytime i do it. Everything else is working fine its just the in-game store. Its been doing it ever since the app update. I did the update and restarted my phone and ever since its had this issue. I have an android phone and not sure if its just me or others are having this issue. At one point the game asked me to clear my caches. So i do t know if thats the problem.