Hot water electrical heat switch problem

[Buckeye Boy]

I have a 2018 Forest River (Wildcat Maxx Lite) Travel trailer. It has a 6 gallon Suburban dual gas and electric hot water heater. The unit has been working fine, but recently developed a problem. I tried to flip the electrical switch to utilize electricity instead of using the gas feature, which I usually do when camping remote. However, the electrical switch at the base of the unit would not turn on to operate. I have seen and tried to push the reset button, but to no avail. Has anyone had this problem and what the underlying issue and solution? Thanks so much for your input in advance.

[Old-Biscuit]

However, the electrical switch at the base of the unit would not turn on to operate.

If that is the OEM Switch in outside compartment....replace it
They corrode as they are exposed to the elements

120VAC from 15A Circuit>>>OEM switch>>>Hi temp T-stat>>>Normal temp T-stat>>>element

Bad OEM switch is common
Hi Temp T-stat trips at 170*F (manual reset)....trips when Normal Temp T-stat fails to open at 130*F and water temp continues to rise
Element....1440W (under oval cover below burner tube....with black/hot wire and white/neutral wire removed should have continuity between the 2 terminals. Should be NO continuity between white terminal and element flange
*no continuity between the 2 terminals...element burnt out
*continuity between white terminal and element flange...shorted

Suburban Water Heater Switch 232259
Suburban Water Heater 120V Thermostat Set 232306
Suburban Water Heater Element, 1440 Watt, 520900