Lost 2.4 ghz channel

8/26/24 - suddenly all my 2.4 ghz devices (printer, smart bulbs) don't connect and it seems the 2.4 ghz channel disappeared.  Anyone else have this issue?  Using FAST 5688W gateway. Tech support says to exchange gateway, but if there was a firmware update that messed things up, won't this be the same with all these gateways?