hmm are there anymore details that you can give us? What year/model is your car? I gather it is just stuck in the closed position and when you press the buttons it doesn't make any noise? There is a sunroof control module above the headliner that could have went bad, or the motor could have gone kaput.
If you pull the headliner down, use a 4mm hex key to manually turn the motor assembly to check to see if the track is binding. If you can turn it by hand, the motor assembly and control module will be suspect. Check to make sure there is battery voltage across the pink and black wires with ignition on.