H4 Approved but EAD pending

I applied for H4/H4 EAD concurrently with notice date of 8/27/19. Unlike most cases, my H4 got approved on 1/14/20 but EAD is still pending as of today.

How common is this occurrence in your experience? How many days should I expect to wait until EAD is approved? What other options do i have?

I checked with USCIS using Emma but they only gave me scripted responses.