@PaulM1972 

Hello Paul, thank you for posting on the TP-Link Community.

Can I know when did you purchase the C80, was it working properly before? Please confirm if you have the same issue if you connect another device to the C80 2.4G network, such as a laptop or phone, monitor the connectivity, then we will know if the issue lies in the router or actually in the smart light itself. You can also install a Wi-Fi analyzer on your phone to review the 2.4G networks around you, then choose a channel that with less interference with others to monitor if the smart light still drops.

If other devices still drop from the 2.4G network, there might be too much signal interference which may cause the signal drops. There are cases that the signal drops or weaken if there are lots of 2.4G signal interfering with yours. Try moving the C80 to open space if possible, you may also try to adjust the antennas on it.

BTW, have you ever tested to connect the smart light to another 2.4G network, will it be stable? What is the brand and model of the smart light?

@PaulM1972 

Hello Paul, thanks for getting back. 

I would also suggest checking the firmware version of the C80, please be sure it's the latest official version. You can either confirm that by logging into the router web GUI or you can download and install it manually from the local official website:

https://www.tp-link.com/support/download/archer-c80/#Firmware

Regarding the signal and speed concern, generally, the higher your signal strength, the higher the bandwidth you'll get over the network, but the speed will be affected by many factors such as wireless interference around your network, the number of devices that are connected to the same network, the total bandwidth you paid for the network, etc. all of these will also affect the actual speed you can get even with the same signal strength. You can go through this article to see if any suggestions will help to speed up the 2.4G network:

10 Ways to Boost Your Home WiFi for a Faster Internet