Is your shower incorporated with a tub? If so, does water flow into the tub?
Please provide a photo of your shower/faucet configuration.
This suggests a tub/shower combo.
https://www.bestrv.com/product/new-2...rbl-2050654-28
In my, quite different, rig, my shower faucet has a conventional stopper on the tub filler that I lift to cause water to go to the shower. The hose to the shower head is "outside" the wall...straight up from the faucet. That link does not mention a shower miser. It's possible that, if you have water to the tub but no water to the shower head, there is a blockage somewhere between the tub nozzle and the shower head. Assuming you have fiddled with the shower head to make sure it's not turned off, that blockage could be as simple as a displaced rubber gasket or a chunk of loose plastic.
__________________
Jim Moore
SW Colorado - 4-Corners Area
2020 Jayco X213 Rear Slide, 2006 RAM 1500 with Firestone Airbags No WDH
400 watts of solar on the roof & 200 watts of suitcase & 2 x GC2 batteries
Starlink Gen-3 running from a 500 watt pure sinewave inverter
Boondock almost exclusively on the shores of
Lake Vallecito