Simple Checks:
* Parking Brake: Make absolutely sure the parking brake isn't engaged. This is the most common cause.
* Shift Lever Linkage: There could be a problem with the linkage that connects the shift lever to the transmission. This could be something as simple as a loose cable or a broken component in the linkage mechanism. Inspect visually if you're comfortable doing so.
* Transmission Fluid: Check your transmission fluid level. Low fluid can cause a variety of issues, including shifting problems.
More Complex Issues (Likely require professional diagnosis):
* Shift Interlock Mechanism: This is a safety mechanism that prevents you from shifting out of park unless the brake pedal is pressed. A problem with this mechanism could prevent the car from shifting even if the lever moves.
* Transmission Problems: Internal problems within the transmission itself are a possibility. This could include a damaged shift cable, a faulty selector mechanism inside the transmission, or even more serious internal damage.
* Electrical Issues: There could be an electrical problem affecting the shift interlock system or other transmission controls. This is more likely in cars with electronic gear selection.
* Faulty Shift Cable: The cable connecting the shifter to the transmission might be broken or stretched.
* Broken Shift Lever: In rare cases, the shift lever itself could be broken internally.
What to do:
1. Start with the simple checks: Release the parking brake and check the transmission fluid level.
2. Consult your owner's manual: It may provide specific troubleshooting steps for your vehicle.
3. If the problem persists: Take your car to a qualified mechanic or dealership. Don't try to force the shift lever or attempt repairs yourself if you're not mechanically inclined – you could cause further damage. A professional diagnosis is crucial to determine the exact cause and prevent potential safety hazards.
Ignoring this problem could lead to unexpected movement of the vehicle, which is extremely dangerous. Get it checked out as soon as possible.