Asus TM-AC1900 User Manual page 95

routers but cannot find your router's SSID, go to Advanced
Settings > Wireless > General, select No on Hide SSID, and
select Auto on Control Channel.
channel in use conforms to the channels available in your
country/area. If not, adjust the channel, channel bandwidth,
and wireless mode.
your router to factory default settings. In the router GUI,click
Administration > Restore/Save/Upload Setting and click
Restore.
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