Experiencing the same issue! I got the Rave Style achievement but no unlock.

Unlocked Dancing Steamwork Style! You danced so well with your mystery dancer, you got an achievement!

Just this got this achievement, and the border's still locked.

got both the achievements but the borders are locked for me too :( anyways I hope it gets fixed soon :3

Just adding my name to the list! I was super excited for getting the steamwork one, only to find it's still locked :(

You've earned the Dancing Steamwork Style achievement!

But still locked 😭

Just posting to say that mine is also still locked.

Adding my name to the list as well - I've unlocked both Masquerade border achievements but the borders are still locked. Thanks!

Adding my name too, got the Dancing Rave Style achievement but the border is locked for me ._. Thanks for helping! ^-^

Just had this happen to me with the steamwork border, frustrating when it took so long to get the achievement.

ohh i was wondering why mine was still locked... adding my name! i got the rave achievement a couple days ago and i still can't use it.

yup! i got the Dancing Rave Style achievement i think yesterday or the day before? but it's still locked for me too and i just got the Dancing Steamwork Style achievement now lol both are locked

I just got the tempest stormy hug achievement and the border is still locked in my wardrobe. It's happening to all borders, not just the masq event ones but could be because of masq?

Dropping my name into this forum too, my Rave Masquerade border didn't unlock after I got the achievement about 10 to 15 minutes ago. I tried Claim Titles to see if that would help but no go, I'll probably update this post later when (or if) that border comes through if it's just a server lag issue. If anybody has a clue how to fix or know what's going on, please ping me! Or message me! It might get lost in my laundry list of pings, but at least I'll have a link to go back to.

Same with mystery dance one...

just got the Blushing Flower Wreath achievement/border and still locked

I also got the Blushing Flower Wreath achievement but the border is still locked.

Also jumping in to report a missing border-the steamwork style one!

Just popping in to say this is still happening. Just earned the Rave border, but it's still locked.

A post was made by Amber on the news:

I am 99% sure Amber meant 'file a ticket'. This morning I filed a ticket and had my cosmetic boarder awarded a few hours later once the appropriate person had time.

If you have not already, and would like your border sooner, rather than later, I'd recommend filing the ticket.

thank you for the info!

edit: filed a ticket and both missing borders have been unlocked!