Device networking issues

What should I do if the device only connects to the 2.4G WiFi band and fails to connect to the 5G WiFi band?

My device had function failure?

Do I need a Zigbee gateway to manage my Zigbee devices?

Why only use AP mode (blink slowly) can add device successfully, but EZ mode (Blink Quickly) does not work?

What devices does the App support? How to add smart devices to the App?

When adding a Zigbee sub-device, the message "Unauthorized, unable to add" appears, and the gateway cannot find the device. What should I do?

How to troubleshoot if Wi-Fi device fails to connect successfully?

What is the specification of the Wi-Fi password when adding devices?

Why the device failed to connect (Bluetooth)?

How to add device in App for Internet connection(Zigbee)?