VW Golf TDI 1.9l ALH - Hatch won't Lock

So I bought my first VW and its a 2003 Golf TDI ALH automatic (unfortunately). I just noticed the other day after having the car for a few months already, that when I lock the doors with the FOB or even in the car, the hatch doesn't lock. So when I got out to the store, my car is basically always unlocked. Is there something I should be checking to rectify this?

Latches break, wiring can get funky, but often it just needs lubed.
Does the golf hatch have a key entry?

it does have a key entry. however, its seized. the key will not go in. I have the inner panel off, so maybe ill start with lubricating it and seeing if that helps. thanks. i really don't want to have to replace the rear wiring harness, but the wires are in pretty bad shape where the hatch pinches the car. and the radio gets horrible reception. so, if lubing doesn't work, i may try to follow the electrical line or something?

The fact that the lock is seized is probably the issue, its probably preventing the mechanism from locking.

If you have the panel off you should be able to see what the latch is trying to do when you press 'lock'. If it cant do that operation something is preventing it, if its not trying to do something then it may be electrical.

ok awesome. ill take a look. thanks a lot! ill let you know if i can figure it out