WAEC hopefuls - 3 times asking for additional docs

Hello house,
I have received request from WAEC on 3 occasions asking for same type of additional docs since they conducted their test in late last year.

Two things (Feb and March) I received the request from an addy with sidmach.com and latest 1 last week from same addy but to be sent to an addy with yahoo.com

Has any1 be getting this? Any1 in the house who is familier with WAEC recruitment procedure; is this their usual way? Kindly respond and/or post a constructive overview on this matter.
Thanks.