Attachment unlocked bug

I recently got fluted barrel unlocked on m433. But when I try to equip it, progress didn't show, and that my level didn't meet the requirements. Attachment shows locked. Also my weapon mastery level doesn't seem to show my progress accordingly with the Exps I gain. Did something happen to the servers or is there another type of explanation? 

Something like that happened with the DSR before, but situation resolved itself after a restart. This one didn't...

I'm on PC, and bought the game from epic games store.