You can search for it at dev.haiku-os.org and if you find nothing, submit a bug report. The worst thing that can happen is we close it as a duplicate, which is still better than people knowing about it but never actually opening a bugreport.
The list of found networks is quite dynamic and changes all the time over here. Maybe reboots aren’t really needed, just keep opening the NetworkStatus popup menu from time to time.
Alternatively, check with ifconfig from Terminal. This shows the found networks (adjust path to network adapter):
For me, not only was a reboot necessary, it had to be shut down cold. Which is interesting, because warm reboot should be the same to Haiku as a cold one, so I suppose it depends on something that’s retained in the adapter hardware (one of the Atheros devices supported early on.)
For me, nothing short of a full shutdown would get me a new list of networks. Not a reboot - shut down power off, so you have to push the button to boot. Like there’s some kind of cache in the card, and it needs to go cold to clear it.
I can’t say for sure that applies to beta2 - I’ve had some sessions that weren’t able to get wifi, and scan came up blank, but I don’t recall trying the all the different reset options. Will try to, next time.