Not Authorized

I have 2 boxes exactly the same so I switched one for the other and got the same results.  Called customer service they said it was on the comcast end but they had to send a tech out to figure out what it is.  I live in an 11 story apartment building , I was watching the tv when the not aurhorized message just appeared.  Comcast seems to be getting worst and worst every year.  I have posts on here about internet that goes up and down like a yoyo.  Now their tv service is failing.  I fail to understand if the problem is with comcast why they need a in home visit ?  All my preuim channels have the same not authorized message.  The local channels come in fine. 3,4,8,13

Now getting CL-17 errors when trying to access on demand .

Streampix plays what ever I select , that is included in my package.  But all the regular not on demand channels some 200+ show not authorized.   When I go to scifi on demand movies which is free with my package all I get is black tv screen and just static for audio.  And again this is the same on 2 boxes ( both boxes are the same model ) that were working just fine hours ago.  My internet is working ok just doing its yoyo thing.

at 11:29am my channels became Authorized agin.  All channels are back and on demand works like it should.