So what you are saying is in the voicemail 72xx exists as the fax mailbox for 71xx ext. ?

My guess would be that the fax DID is routed directly to 72xx which is cfd all to voicemail (200)

Since the pbx won't let you fwd 7213, maybe it doesn't exist?

Just a guess.

In the PBX programming it's Prog 24-09, to set call fwd - if that helps.

What happens if you dial 7213 from an ext? if you get an error tone it isn't programmed.

D