Why did the prophet Elijah ascend to heaven, if God said no one hasn't gone to heaven except the Son of Man?

No this is actually quite simple the word for Gone up is Anabaino, it is a word signifying the action of going up, so what jesus was saying was no one can Go up by their own actions, only by God can one enter heaven, God sent a Chariot of fire to get Elijah, and He Himself took Enoch.