BE9300 - Cannot connect any device

The web interface allows the user to control many features which the 'app' does not.  Use a device with a screen larger than a smartphone (computer, laptop, tablet). Connect it to the RS300 router with Ethernet or WiFi, and follow the directions on page 71 to log into the router and set the Security level to WPA2-Personal.  Even though the default setting of WPA2 and WPA3 is supposed to be compatible with almost every device, there are some devices that simply balk at connecting when WPA3 is enabled at all.  Just click the appropriate box on the screen. and then "Apply" at the top of the page.