Well, I’ll jump in here.
Chances are your H26 110v system was added after the original purchase.
I’ve not seen one with 110 from the factory.
The dealer may have installed it, but I would suspect an owner did the work.
So, get yourself a simple tester. One with a light that comes on when current is present will be fine.
Start at the source – literally. Test the end of the shore power cord. Then the back side of the power inlet. The power panel and fuse. (I guess I’m making an assumption that you don’t just have an extension cord thrown in over the side as some people do. If so, shame on you). Pay particular attention to connections and fuses.
Have fun! It’s a great way to get to know your boat.