1. The network cable plug connected to the set-top box is loose or dropped.

Solution: Reconnect the network cable to restore the signal.

2. Set whether the router of the wireless network is turned off or the wireless network is not turned on.

Solution: Turn on the wireless router and other devices detect that the wireless signal is normal.

3. The input TV video source of the network set-top box is inconsistent with the current TV signal source.

Solution: Adjust the TV signal source to make the set-top box video source consistent with the TV signal source.

4. The network port module of the set-top box is broken.

Solution: Let the professional master change the network port.

5. The wireless function of the set-top box is not turned on.

Solution: Turn on the wireless function of the network set-top box.