Hi so I turned on my game and noticed that my Spartan was reset and my campaign saved games were deleted. What happened?

It’s a common issue with Halo 4. Sadly all you can do is reselect your armour and replay the Campaign to unlock the levels.

I’d highly recommend deleting your profile and redownload it if it’s an Xbox LIVE one, it is possible your profile is corrupt.

I’ve also had this problem twice. I deleted my account and re-download it, but to no avail. I’m starting to think it a regular thing. It’s a pain to beat the campaign on legendary solo.