Hi, @benconc
We would like to welcome you to the king community. Thank you so much for being willing to joining 😊
We're sorry for your problem. In fact the game is getting bigger with each new updates. So the device's RAM (random access memory) should be kept free to play the game healthy. Receiving phone calls during game play puts a lot of pressure on the RAM and can crash game app at any time. For this you can lose the stored boosters.
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