Monitor wont tilt

Since you have already tried the screen tilt settings, the problem may be in the gears for the mech. There is no easy fix without being able to check it out in person. It can be a very big job. Unless you are familiar with disassembling these type of units I would advise against trying to fix it yourself.
I have repaired a few of these and they always takes over an hour. And that is knowing exactly what I am doing.

It has a couple of gears and a motor that move the display in and out. To get to that mech the unit has to be taken completely apart. It is on the bottom of the unit under the main board.

It could have a broken gear, debris stuck in one of the gears teeth, or just an alignment problem or something bent out of place. In any case, it takes some experience to figure it out.

wish I could have told you an easy way to fix it, but I don't know of any quick, easy fixes for it.

Best bet is to take it to an authorized Kenwood repair center to have them look at it. You should be able to at least get an estimate pretty cheap.