99 astro rear lock problem

After I have unlocked the doors via remote and go to push the button on the rear hatch door with our thumb or any finger for that matter as to open, all doors lock inlcuding the rear hatch. Meaning I can not open the rear hatch.

Now if I unlock all doors with remote then I take door key insert in rear hatch lock and push with key no part of thumb or finger, you are then able to pull hatch open....:banghead:

any ideas as to whats going bad anyone?

check fuses with a test light. lock and unlock circut use several fuses and relays. if fuses check good swap relays owners manual will provide location