"Dedicated to Crimson" Achievement Glitched

I have beaten every Spartan Ops mission in all current episodes (1-5) and never got the achievement. I have even tried conpleting episode 5 all over again. Anyone know what to do?

It’s a known glitch right now.

Simply replaying the very first chapter (Ep 1, Ch 1) on any difficulty seems to unlock the achievement.

Cheers!

And do that first mission “Solo”. Not with matchmaking.

Then it should work.

Same thing happened to me. Look back to Ep.2, it said I had none done (even though I beat all of 'em on Heroic) went back played the first chapter and boom it unlocked, looked back in the menu said I did all of them on Heroic (which I did). Its an annoying glitch. When I finished Ep. 5 I was look here it comes 80G! And then nothing happened, dont worry though, just look at the recent episodes.

Didn’t happen to me, if it did then i would just replay the episode/s.