Actually, @EA_David was not incorrect. I have, so far, perhaps 4-5 milestones 'frozen' to include the final NT-242 milestone and the initial S-5 milestone, but I have not encountered a newly frozen reward in some time; since the advent of the problem, I have been able to unlock two attachments for the FWMB heavy weapon and at least one for the Blrrg pistol.
Yeah this has NOT been fixed. I still have the first 2 mods for the NT-242 unclaimable, yet I was able to claim the 3rd and final without the first two. Still not fixed. Ridiculous. And you want to turn MTX back on when the game is in this state. We've paid for a game that's still in Beta.
