Since this is new to you it is very likely the issue always existed and you are just discovering it now. You can find out if this is true by plugging into a campground outlet but the testing procedure can be deadly. Take off your shoes and touch the skin. Please don't do this!
I would suggest you get something like this Fluke non-contact voltage detector.
Fluke TesterWith this device you can test the outlet. If that's good you can work your way up the power source. Test the extension cord if you use one. Test the transfer switch if you have one. Test each outlet inside the coach. If you find power where there should be none you may simply have a reversed wire in the circuit somewhere. Do a Google search and you will find information like this.
RV "hot" skinTake this problem very seriously and be sure you find and fix the problem.