Loosing Channels

Hi all, hoping someone has some answers I have the Limesat AIr and yesterday, I lost a ton of channels. I rescaned figuring I must of hit something on the remote that was laying on the couch. Everything was fine after that. Today, I had the TV on and went out to do some yard work and when I tried to scan for the EPG, I got a message that the channel was not available. Say what? So I pressed the guide and the only channels showing in the 100's range, was 118. Anyone know why this could be happening? I do have a laptop fan under the receiver. I don't remember this happening before and I've had the receiver I believe a couple yeas.
Thanks