DIRECTV is in the process of updating some of the channels.
Right now the following are down:
1229 HGTV
1235 Esquire
1236 E!
1266 FYI
1271 H2
1284 Science
1356 MSNBC
1588 Uncensored TV
You can still download the VOD content for these channels via Smart Search, the apps and DirecTV.com