* Stuck or jammed mechanism: The release lever inside the vehicle might be broken or stuck. Try lubricating the mechanism with WD-40 or a similar lubricant. Sometimes, firmly pushing and pulling on the lever repeatedly can help free it up.
* Broken cable: The cable connecting the interior release lever to the fuel door could be broken. This requires accessing the cable and either repairing it or replacing it, which is a more involved process.
* Door itself is jammed: Debris, ice (in cold climates), or something else might be preventing the door from opening. Carefully inspect the area around the fuel door for obstructions.
If none of these solutions work, you'll likely need to take your Jeep Liberty to a mechanic to diagnose and repair the problem. They have the tools and expertise to access and fix the internal mechanism.
