How can I reset my Lumia 640 XL?

[Windows Central Question]

Lumia 640 XL

I have a brand new Lumia 640 XL. This morning the following started happening. After 5 minutes the screen saver comes on, no problem so far. But when I want to use the phone again, I cannot "restart" the phone, Screen saver stays on and the phone is totally unresponsive. I take out the battery and reinsert and then all works again..until the screen saver comes on again... I have had the phone for a week and the problem started this morning..
Thanks !

 

[N_LaRUE]

Try a soft reset and see if that helps.

Soft reset -> hold volume down and power button until phone vibrates. Phone will restart.

If that doesn't work you may have to hard reset unless you've added an app that effects the lockscreen?