My mincraft randomly keeps on going off the game a back to the launcher like every 30 minutes

My mincraft randomly keeps on going off the game a back to the launcher like every 30 minutes

*What I expected to happen was not to shut down a go to launcher

*What actually happened was it did shut down a go to the launcher

Steps to Reproduce:
1. go on minecraft
2. and then it shutdown and goes to launcher
3. ...