Campaign data lost, need urgent help.

Hi guys, first of all, thanks for reading this it means a lot.
Okay so I had passed the campaign on normal and was progressing through it on legendary solo. But then the other day I went onto it and I only have the prologue to start from. I go onto waypoint and it still says I have completed 8/8 missions, but I was making my way through legendary.
Anyone know how to fix this or having the same issue? Thanks in advance.

I have just had this exact same thing happen and have posted a similar thread. An update wiped my campaign progress, but allowed me to carry on from where I was. Finished that campaign on solo Legendary and didn’t get the achievement! Checked on Waypoint, and it says I’ve done all the levels.
Did you ever get it resolved?

Bump, because I have the same exact issue.

…Except I already did it Legendary solo, but the only achievement I need to finish off the game is Bromageddon. I did four missions on Heroic with a friend, then jumped on later and I could only choose the prologue, absolutely nothing else. I did some minor googling and someone said it could be an issue that has to do with H4 being installed onto the hard drive (which I do, for faster loads of course) but nothing confirmed.

Any solutions? Others with the same problem?

This happened to me yesterday, after the crimson map pack went up on the marketplace. I had finished campaign solo on normal and was working on the legendary run through, luckily my checkpoint from the forerunner level was still valid, but whatever is causing this needs to be addressed. I’m tired of having my armor and loadouts reset, or my campaign progress erased. Oh this also occurred a couple days after I started working on my specialization.