The fuel cap won't open

Since you didn't tell us what year your Freelander is, I may not be giving you 100% accurate information, but in general the first thing to do is check the fuse. Does your tailgate work? If not, fuse F25 should be the one that controls power to the fuel door and the tailgate, so check that first. Double-check the the fuse diagram in case your year is different from the reference I used.

If that doesn't help, the solenoid may be stuck. Try gently pressing in on the fuel door while clicking the lock/unlock buttons on your remote or on the dash. That can sometimes free up a sticky door.

Since Land Rover didn't see fit to include a manual emergency release, you're left with accessing the fuel door mechanism itself to get it open. You'll have to remove the passenger side rear wheel well liner to get to it. The actuator motor is located on the inner quarter panel behind the fuel filler neck. Manually move the locking pin back from the support bracket lever to release the flap.