It's hard to diagnose your problem from what little you've provided. However, my first suggestion is to look for a circuit breaker or two inside the campground pedestal. Make sure it's turned ON.
My 2nd suggestion is to get yourself one of these 120VAC outlet checkers from Walmart
and one of these 30 amp to 15 amp adapters from Walmart or your local RV dealer (or even the campground store)
Plug the adapter into the campground pedestal, then plug the circuit checker into the adapter and make sure you're getting proper 120VAC from the pedestal.
Finally, make sure the main breaker is turned on in your camper. Open your fuse panel and check the breakers.
More detail about your problem would help. I initially read you post to say you never had AC, but on second reading, it sounds like you might have had AC for a while and then lost it. If you had it and lost it, I'm guessing you tripped one of the circuit breakers I've discussed.
Note: If you are running the AC, don't try to run the water heater on electric, the fridge on electric, or the microwave (or a toaster). These are all high wattage (i.e., high power, i.e., high current draw) devices. If you have a 30 amp system, trying to run the AC with any of these will almost always trip a circuit breaker.