Help, Skipped main mission

Hello,

So I have an issue, I was at a certain mission in the main story, i logged out of my game and entered into my friends game who was a chapter ahead, he completed a main mission just as i logged in. Now my game has updated to his but i am missing a a whole chapter when i go back to my game, and also a planet that I can not go to, i dont want to write any spoilers, but this is it:

SPOILERS:

My mission was to go to Athena, he had been to Athena and finished that mission, now Athena is not in my fast travel.

Has my game bugged out? and am I stuck and not able to go there now??

Playing on Xbox one

Thank you for any help!

UPDATE

SPOILERS:

For anyone else this happens to, I loaded into my friends game when he was on Athena and then that opened it up to travel too, sadly i didnt get to play that chapter, but he explained to me what happened.

Hope this helps someone else out there

Hopefully this will be patched soon. certain things you cant really test for in a perfect environment.