I am getting this a lot. It stops automation. It is not true because if I just run an OQ task again it equips the outfit and continues.
I think it happens when a new area opens up and the first OQ task attempted is to adventure in the area.
Most recently, I manually leveled to Level 10. (Manually because OQ no longer offers a leveling step, see other reports about missing tasks). The S.O.CK. task did not appear upon OQ refresh so I manually adventured for and used a bean. The S.O.C.K. task appeared. I tried to execute it and got the message. I tried again and thigs work as expected.
I don't have an outfit named underwater and the Sea is not unlocked unless it is a side effect of something else that I haven't noticed.
That error will show when a call of
outfit(<your default outfit name>)is returning false. If mafia returns false despite your actually being able to equip the outfit, I believe that's a mafia issue? Can you test this from the CLI ("outfit" command) at a time when you're running into this issue with OQ? If mafia's outfit command won't equip an outfit that you can actually equip, I'm not sure I can do anything to fix the issue.