BlackBerry Priv: Call Forwarding not available

BB Priv unable to forward calls out to another number.  Error message: "Call Settings Error:  Unexpected response from network."  This appears to be an ATT side issue to accept the redirection.  I have no clue why ATT does not support standard *72/*73 call forwarding.  If I can't get this cleared up, I'm going to have to port my number elsewhere...and leave ATT, which I really don't want to.  Due to work, I have to toggle between a Verizon Pixel device, which allows a nicely separate personal partition so that I don't have to carry two different devices during the week.

Android 6.0.1 (Priv can't update past Marshmallow), Build AAW068 (updated 20AUG18).