Why are origin x-men stuck

In the All New X-Men, Hank cannot, for an unknown reason, use the time cube to send back the original X-Men. But Magik has the power to phase through time, and can bring others along with her when she teleports, so why doesn't Magik bring them back

Because its Bendis and that would make too much sense.

Because something, (possibly connected to Age of Ultron) is preventing time travel backwards pass a certain point and the O5 were here already when that lock was put in place....I think if you read New Avengers you'll see its connected to The dimensional breaks that allowed Galactus to enter Ultimate Marvels Universe

Yeah, it's probably a consequence of Age of Ultron, allthough never actually stated (I think). Wish I could forget about AoU...