When you push the button with your index finger, use the rest of your fingers to lift up on the cover. It should come open then. It was never designed to Pop Open when the button was pushed. Some are more stubborn than others, but they only pop up slightly. Sounds like yours is normal.
Agree with the others. Push the lock button and lift - no popping up on its own. Also as mentioned above, once it is open, if pushed all the way back, it will "latch" into the open position until you close it. Seemed like there was a concentric holding it up, not a latch per se.
Mine used to "latch" into place, but now does not do so. I'm fearful of pushing too much in case of breakage (seems somewhat fragile), so now I just hold it up while retrieving the object (pen, map, etc.) from the cavern.
Speaking of which, it is not cavernous at all, (neither is the glove compartment or the door "pocket") so storage of objects is very limited. urple: