I've started knitting a hat in the round and just noticed that I have a twist. how do I fix this?
Do you mean you joined it twisted so that it's shaped like a mobius instead of a ring? If so, if you'd done more than 1 round, I think you have to frog.
Yep, if you're still on the first row, you can kind of straighten it out, though the CO at the join will be sorta strange looking. Since it's a hat and not a sweater, maybe go back to the CO and straighten it out.
I just did it the other day for the first time. Frustrating, but it's good that you noticed it early on. You can't fix it other than starting over again.