Your network is offline error 99999

Xfinity streaming app on my TCL Roku tv has repeatedly had a black box with a message saying that the network is offline however content both audio and video are streaming and I can change channels but I can’t see picture due to black box overlaying streaming picture.

Turning tv off and on does not solve problem.  Also loaded a different app then went back to Xfinity app and still had problem.

How do I solve this?