Something is causing the 22khz tone to not make it to the built in switch in the LNB, or the switch in the LNB is not responding to the 22 khz tone.
Let's do the process of elimination...
shouldn't be a line of sight issue, whereas it is possible to lose just the one satellite to line of sight issues, the 110 only being out is rare and pretty obvious if it is blocked.
Are all three not getting 110?
If yes, check your settings to make sure you have the OVAL-3 dish set as your dish, the Oval-2 dish only has sat A and B, 101 and 119, with an optional sat C, 110, so that would also explain it.
If you have it set to Oval 3 and there is no 110 on all three boxes, your problem is NOT your boxes.
Next Question..
When you installed it, did you use new wire? or existing wire.
Whereas it is very rare, occasionally some wire or connectors, will not pass the 22 khz tone that makes the dish lnb switch to the sat c, or 110.
that is the rare instance...
If you feel the wire is perfectly fine, most likely, and all the above didn't fix it. Try a new LNB, either check eBay, or someone on here probably has one they can get to you for real cheap, I know I have about 10 extras laying around my garage.
Also, do you even need the triple sat?
Speak Spanish?
Locals on the triple sat in your area?
Speak Chinese?
Using an older HD box?