Ability to save mission progress when in co-op mode

Xbox One S (though I believe it’s across all platforms)

I haven’t seen any posts on this issue, maybe I haven’t looked back far enough, but in order to complete missions on co-op and have them save to you own game, it says you need to complete the mission prior to the one you’re going to do, on your own game first. Then, if you have that done, when you do the next mission on your friends map, it saves it on yours, but if you continue on to the next mission after, it says it won’t be saved to your campaign? So in order to continue on with mission progress you have to go back to your own game, and do the mission again.

to make it fair to players who join a co-op , you cannot progress missions in a co-op unless you are of the same or higher mission progress than the host. Why ? , this stops a player entering a co-op game and having all their missions automatically being completed. the best solution is to do missions on solo , or have a few friends that will all play at the same time to do missions together. hope this helps clear up some confusion.