Steam achievments lag

I played 1722 hours and steam lags and won’t to give “One Month” achievment!

Here’s achievments menu

(It’s grey means that’s not done)
For dumbs:1722 : 24 = 71,75 71,75 : 30 = 2,391666666666667
So i played 2 months already

I had a lag that took 10 minutes to archive something, till I reinstalled Steam and everything worked fine again.

But that it does nothing at all is weird.