Couple things to check..
Channels 480 - 481 should confirm b-band converts are working
Channels 490 - 494 will confirm voltage is being properly passed through your lines.
If any of those go to SFSS then there is a definitive problem somewhere.
Look at all connectors and make sure the Dialetric is even with the connector. Make sure the Connector is a blue band or black band compression type and not a crimp on. The stinger should be 1/16- /18 " out from connector/
Make sure your cable going to your HR is 3ghtz or better rates (2.2ghtz will work but with any kinks/compression in the line you will loose or have issues on channels that sit at 2150mhtz. Make sure it is RG6 or better and not RG59
Verify any splices in the cable that they have weather boots, are tight and have not rusted. (if the semi-conductor is rusted you need to get the line replaced with solid copper, and not copper clad)
Verify the connectors on the Groundblock/Multiswitch are as stated above and have weather boots. Make sure the lines at the GB/MS are not crimping themselves.
And make sure the 5lnbf dish is aligned properly with a signal meter and the tech uses the fine tuning dials. If its on a Pole make sure the pole is concreted in secure and is perfectly level. If its on a Mount, make sure you have mono-poles and they are secured.. the top part of the mount should be perfectly straight. a Properly mounted dish on a roof should have zero movement from the dish to the roof, the lnbf arm will move though, you should feel confident that you could use it to rappel from
Most of this you can verify yourself. But you may have to go under your house/attic