Some channel unable to view?

[Salad1]

Recently we are unable to view channel 105 and 402 and not sure why and how to fix it? 
little box on right of the screen say mini tV unavailable No Satellite signal, all others channels can be viewed?? 

[Annie+UK]

Please Note: Sky+ is now a legacy service that Sky are winding down

"No Satellite Signal" is an error generated by your Sky box, it has nothing to do with broadband (Internet connectivity) and usually indicates an issue with one or more of the following:

• The Dish is misaligned (not all transponders are getting through, thus some channels may be affected and others not)
• The Tuners in the sky box
• The input sockets on the Sky box
• The plugs on the cables
• The cables themselves
• The Sockets on the dishes LNB
• The dishes LNB has gone faulty for the connections the box is using
• You have plugged your Sky+ box into a dish that is only compatible with Sky Q

You may have to call out a local satellite installer, unless you have Sky Protect insurance, to check/fix your system, another option is to move to Sky Q, as during the move all issues will be resolved as part of the install, there is also the option of Sky Glass or Sky Stream, if you want to move away from satellite TV and use the Internet