Hot water heater

I assume yours is a gas-electric HWH. If so, did you have it set to run on electric, or just on gas? We have had problems with past HWHs not being all that reliable on gas, but they worked ok on electric. Perhaps you need to set it on that instead. There should be a switch on the outside of the heater itself, plus one in the circuit panel. If it's a gas-only heater, then you may just have a blockage of the gas to it - spiderwebs are a common cause of that and can be cleaned out. They make special tools to do that (not expensive) which most RV supply places would have.

I'm not sure what HWH means, yes I tried both switches and the lights on the switches do not go out, I checked the breaker and it was good. Don't know where to go from here.

Be sure to turn off and wait a few minutes for any gas to clear before attempting to restart. (I learned this lesson the hard way).
The hot water heater is not something to fool around with so be careful. Take to Camping World, they fixed mine in no time flat. Now it always lights.

What brand of water heater is it? (HWH= hot water heater).We need to determine what you have before we make wild guesses to help you.
Did you have water in the heater tank when you turned on the electric?
Suburban has a switch in the outside compartment for electric.
Did you have propane flow? We always light a burner on the stove to verify air is purged from line.

HWH in this case is a hot water heater although I never understood why you would want to heat HOT water. Water heater I get!

Need better info.......

All we know is that it is a combo water heater and doesn't work

Is it an Atwood WH?
Is it a Suburban WH?

Different brands......different methods used by mfg.

Let us know which brand so we can help

I guess OP figured it out?