HBOMax cannot access with top set box

For weeks, we cannot access HBOMax via an Xfinity top set box. We keep receiving error code Apps 04036. We restarted the  top set box, modem, unplugged all components , cleared history numerous times, but we are . Still having this problem . However we can successfully access HBOMax on our other  2 SMART tvs with their remote boxes, as well as on our iPhone

anyone else having this problem? 

Any solution? Any explanation what went wrong?