I have been receiving calls labelled as Comcast 844-250-8578. From other forums here, I see that these calls are generally about connectio issues. However, I use NoMoRobo, which is recommended by Comcast, and it blocks the 844 number. Is there something of concern I should know about?
The call is probably legitimate, but rather than calling that number, it would probably be best to follow the advice in https://forums.xfinity.com/t5/Home-Phone-Service-Equipment/Comcast-robocall/m-p/2952624#M2945.
Comcast Customer Security Assurance can be reached at 1-888-565-4329 (from https://internetsecurity.xfinity.com/help/report-abuse/).