Not sure how you tested it. I would try two different 12v items and if neither work then there is a problem.
The caravan will have a battery check provision which should be a push button on the control panel. That will either show the voltage at the battery or light up red for flat, green for fine or amber for fair. I am not familiar with your models electrics so do not know for sure exactly what you have. If the battery is OK check the fuses but after that unless you are competent with the wiring I am afraid you probably need professional help.
If it’s a Sargent electrical control unit it should have a small dark push switch over the 12 v fuses. Mines an EC 400 and that switch has to be pressed in for the other control panel to show any information. With that switch “in” you can then use the controls on the display to look at battery levels, pump on/off etc.
If it’s similar to mine that switch also has to be ON when towing.