On the level that you first get the hummer i parked it in the garage right before the first gate and now its stuck. Is there a way I can get it out or restart the map?
Looks like the old "Ceiling-is-too-low" bug that appears in the Retailer of FOT. Try installing the patch, it should fix it (although I thought it only applied to the APC)
If that doesn't work try leaving the bunker and re-entering it. If THAT doesn't work blow up the hummer and go with the APC which you get later :-p