Unable to connect to Achievement Server + Achievement number not shown

I was mapping with my other 2 friends, we killed the unique with onslaught, which was the challenge, instead of getting it, we got a error saying unable to connect to achievement server.

My friend took a divine shrine right after, got the same error message but no challenge.


Could you fix it??

P.S. I found Drillneck quiver in the same map, please don't roll back server, thanks!!