My Lumia 625 touchscreen is broken.display is coming randomly, how can I fix this?

[Windows Central Question]

lumia 625 touchscreen is broken.display is coming randomly.how can i fix this?

lumia 625.slipped from hand.touchscreen is broken with cracks.display is coming randomly.sometimes it comes,sometimes it doesnt. phone working perfectly without display.calls are coming smoothly.do i need to change the digitizer or the lcd+digitizer ?