Trouble setting up Tronxy xy-3

[K_D_129 0]

New to printing and just got a tronxy xy-3. Having a few problems getting it dialed in. It's printing roughly 10 mm above the bed...sometimes. I'm not sure what I need to change but sometimes it will print above the bed and sometimes it will come down to where it should be. I have printed a few things...when it gets down to the bed. And they come out decent for now. If i move the Z axis and then try and print, It asks if i want to print from the current location. I'm using cura to slice. We 3D print where I work so I have a general idea of how to set the settings and how it should be printing. The magnetic bed also might not be the best for adhesion, has anyone else had adhesion problems with magnetic mats?