NULL portal in sanctum

I just killed Varaketh in Sanctum first floor and upon entering the reward room after getting my rewards I see that the "Forbidden sanctum" succy portal is instead named NULL and can not be clicked to go back to the Forbidden Sanctum. This didn't impact me because I can just exit to character select and come back in, but it was weird. https://imgur.com/NU6AbNL
Bug report reference number 1,658,590,224

Same issue for me except after second floor boss kill. 398805457.
https://imgur.com/a/awRvWFO