help with Water Heater

That little toggle switch in the lower left hand corner of the heater is likely bad. Too small an amperage for the job and subject to moisture. I know that was my trouble, intermitant heating. I jumpered it out and use the curcuit breaker to turn it on and off.

You have a Suburban 10 gallon Electric and LP water heater.
Based upon my experience, I would remove the black plastic cover with the two rubber buttons that say reset.

On the left side is the electric thermostat and high temperature limit switch assembly. You will probably find that the lower terminal on the thermostat is burned and barely making contact.

If bad, replace the thermostat assembly. It is held to the tank with one nut. Remember to turn off the 120vac power before removing the thermostat assembly.

Thanks, I know very little other than it's a dometic 10 gal. model sw10 DE.
don't know if it operates on 2 different thermostats (gas & elec) or one.

Need Make and Model to even hazard a guess. For example, if it's a Suburban, the LPG and 120VAC operation are separate to the point it might as well be an LPG heater and an electic heater sharing the same tank. OTOH, Atwood operates the two modes from a pretty much integrated control system. Give us the details and somebody can point you to some good troubleshooting.