There are 2 different voltages at work here, AC voltage and DC voltage. AC voltage will run things like air conditioner, microwave, and outlets. DC voltage will run lights, water pump, radio... Turn off your inverter and turn on the battery disconnect (red handle wont come out) and see if anything is working. Is the main breaker on at the pedestal where you plug in the power cord?
You can call the office at the campground you are in to see if the maintenance guy will check the pedestal for power if you don't know how to check it.
Steve & Patti
2018 Grand Design Reflection 315 RLTS
2019 Chevy 2500 HD Diesel Z71