"I am a man, but not a woman."
Translation:Ego sum vir, sed non femina.
All possible word orders should now be accepted (there are no less than 552 translations currently entered in the Incubator). Unfortunately, it takes time for the answers we add in the Incubator to begin to be graded as correct, sometimes two weeks or even longer. Please still report if your correct answer is rejected though (with the button in the lesson, not in the sentence discussion), it's possible we missed something!
There's a guide to effective reporting here which you may find useful. :)
I don't think 'but' should be used here. "I am a man and not a woman." seems logically better. To me, 'but' is used like "I may be X, but that doesn't mean I'm Y." "We won the battle, but we lost the war." "We are successful, but we are not happy." The sentence should really be 'I am a man and not a woman.'