2010 Chevy Cobalt LT Sedan - trunk latch?

[Woogeroo]

So, my sister has this 2010 Chevrolet Cobalt LT Sedan... and it has this issue here :

The issue is when the key is put into the trunk latch keyhole, the key will turn but the latch will not disengage to open the deck lid.

It's only a sometimes issue, I'm guessing some lubrication wouldn't hurt, but thought I'd ask about anything else to check... or to see if this is a common issue with this model?

--

I asked around on another Chevy related forum, that has a car section, but no replies yet. Thought I'd ask in here, as some of you folks are mechanics/dealer folks. I've poked around searching online, haven't hit the right search string combination yet I suppose.

Thanks a bunch,

-W