Game is played for about 5 minutes and then disappears from the screen

I play the game for about 5 minutes, and then the game disappears from the screen.

I then see a little gray box on my taskbar, and I push it, and then I have to wait for Mohang to completely restart again,.

It also happens on my other PC. I can't understand why no one reports this..

It has been this way for about two years now! So my grandsons can never play minecraft anymore.