When you get lagged or you get lagged while loading, it kicks you out of the game

I am lagging sometimes while loading in minecraft. Even on store. Even I type slash, even I turn off my phone and open it again, and even I close and open it again (Not To Restar). It just kick me out of the screen menu like this is very frustrating bug I have ever seen to all bugs that I have encountered in the game. Yes it is called the game crash. But please fix it. It is always encountered every time when we load. I hope it will fix it in the next version of minecraft