@alil2096
So, after home process, I have all axes in 0;0;0 …
… where Z=0 is at the bottom of your printer, right? Well, in order to print, the bed must be near the nozzle, that is, the first layer is always printed at (or near) Z=0. For each additional layer, Z will be incremented, which translates into the bed moving down.
Of course you can have the Z end stop at the bottom of the printer, but this determines the maximum Z value (390 in your case?), whereas Z=0 must be at the top.