Thanks I have been working with them this week. They are also confused

Thanks for your time be gentle I am a total newbee Just bought 2 new m2s V4 one printed right out of box. Other one hunts for home on the z axis and if I hit 100 or -100 I get the same result down. Gets hung up at bottom and you have to spin the knob to get it started. Some times goes to home at top...