I recently used a tablet running a wifi analyser to help my daughter get the best wifi signal around her home.  Discovered that 2 or 3 neighbours were using the same channel as her router, so we changed the channel for less overlap/interference, and obtained better signal strength.

However, when I ran my analyser app again, I could no longer see her network ... even after a reboot and several minutes her network would not show on my tablet.

The network was still perfectly available on her laptop, and using the smart TV simply required a network search reset to find the amended channel.

Can anyone suggest why I couldn't see the network on my laptop after the channel change?