We have a 2018 RT29S. Last summer our microwave and outlets didn't work underway. They always had prior to this leg. We were headed to meet the RT gang at Comox, so I asked them to come look. everything was "normal" when on shore power - but no 110v from the inverter. Also, no error codes on the inverter panel.
To shorten the story, Kenny and Andrew visited my boat and tried "a bunch of stuff" with no change.
Andrew was going through the menus on the inverter panel and discovered that my inverter was "set" to be a battery charger only..... He corrected that menu setting and all has been fine since.
I took the blame for changing the setting, but if I did, I have no idea when. Maybe I bumped it loading stuff in the cave??? Maybe I shut it off and clicked the button in the wrong order?? I really don't know.
My advice would be to get the manual and check the menu settings on the inverter...… One other thing that sounded likely (but wasn't our problem) is the outlet on the inverter - it has GFCI breaker....Try resetting that as well.
I hope that helps.
Rocky