hi
park brake fault usually occurs when the battery is low, low battery effect all modules on the car, if battery voltage drops too low, the modules go into fault
make sure the battery is also fully charged, left on charge over night
you get fault if either, the calipers hand brake arms have gone stiff, handbrake cables have gone stiff or epb motor has gone tight, ideally you need to get it plugged into to Jaguar ids/sdd which will tell you what the exact fault is
you can quickly reset the epb module by unplugging the epb module in the boot for about a minute, when you plug it back in and switch the ignition on you should get the calibration message
you can also drive the epb motor manually with 12 volts to make sure it works and sound ok and may also free it off,
have a look at this video on how to https://www.youtube.com/watch?v=8xebdRYwtjE&t=3s
also if your boot gets lots of damp, as some suffer with water ingress, it may have a faulty epb module
cheers
Joe