The conjugation for the third person of the verb "bleiben" is "bleibt". Then why is the Bach's composition "Jesus bleibet meine Freude"? I know this has nothing to do with this sentence but I have always had that doubt. (I'm not a native english speaker so sorry if I have errors)
What was your full sentence? If it was "Ich bleibe nicht", then it's wrong because it's not future, but present. If it was "Ich werde nicht bleibe", then the sentence is grammatically wrong as you already conjugated the verb "werden", so the second verb "bleiben" can't be conjugated anymore
I'm a native English speaker, and as such I have a difficult time expressing things in correct grammatical terminology, even though I can tell what's right and wrong :P
Your sentence seems to be 'present continuing': You are not staying there now, and you will not stay there in the future. You might say this if you were in the lobby bar of a hotel just for a drink, and someone asks you what room you're staying in. "Oh, I am not staying here. I just came for a drink".
That said, it could be used conversationally to have the same meaning as "I will not stay here": You're looking for a place to have dinner with friends, and just walked into a restaurant that smells terrible. You say "I'm not staying here!" to express your decision to leave and find another place. But, I think that as with any translation that requires a paragraph and an elaborate story to justify, it's probably not the best choice.
I had the realisation that you can say it, if the future time is specified. "I am not going to the meeting next Tuesday" seems fine to my ears. If the time is already established in conversation, you don't need to repeat it: "Will you be there next Tuesday?" "No, I'm not going".
I think it's probably just a lazy shortening of the more correct form: "I'm not going to go".
My translation to English is exactly the same as Duo's. Yet the system keeps on refusing it!
Perhaps you had a listening exercise instead of a translation exercise?
Can you show us a screenshot, please, showing your answer and the error message? (Upload it to a website somewhere, then add the URL to your comment.)