Hi Trev,

If you cannot control the lights by the smart switch, please check if you are on the latest firmware,

if it's not latest , please upgrade the firmware , about how to upgrade the firmware, you can click on the following link to get some help:

 

https://www.tp-link.com/us/faq-2325.html

 

And you mentioned ,you have a new switch, if you use the new switch, to take place the old one, it doens't work either?

 

Yes, you can try to use the normal switch and test if it can work fine.

 

Merry Christmas.

if by "replace the nonsmart switches" you mean change those to smart switches that will have no effect. If you replaced the old switch there's a small chance the new one is broken too, but more likely the wiring isn't correct. Double check that all of the wires are touching and tight in their connectors, and that you swapped the right ones over. You're sure the old switch was broken, it's not the fixture that failed? Was it still clicking when activated?