Black Switch (LZW 30) not turning on light

I installed a LZW 30 black series switch over the weekend. The blue light is on, I can pair it with my SmartThings hub, and when I turn on or off the light I hear the click of the switch and the blue lights changes color. So I believe that tells me that my line and neutral cable work perfectly fine.
The switch is in a 3-way setup with a dumb switch.

My problem is that the light never comes on. I checked the bulb and it’s fine. I re-seated the air gap without fixing it. I pressed the Config button 8 times which didn’t fix it either.

When I installed the switch first it was working fine once or twice. I reseated all cables several times and checked that they’re properly plugged in. No Joy.
I tried with the dumb switch in off and on position. No Joy.

I had a similar problem with another switch earlier and used another one in that situation since I purchased 7 switches. That switch then worked just fine the next day. I don’t know what fixed it.

Did anyone else have this problem? Any idea what I could try next short of buying another switch and replacing it (or asking Inovelli for a replacement)?

It’s really weird. Everything’s looks correct but it doesn’t turn on power to the light. Like the air gap is not working or something else is locked which prevents the actual physical switch to turn on. It looks like it’s stuck between the line and traveler wire so neither one has contact.

Can you post pictures of both boxes with the wires pulled out the switches connected?

A few times I have seen my three way switches indicate that they are operating when they are not, but only a few, and always fixed by an air-gap reset.

Have you tried removing the second switch from the equation entirely? Do you see the same behavior when physically switching and when z-wave switching?

I didn’t try without the other switch. It’s a dumb switch which only connects the line feed with either the load or the traveller cable. I know the dumb switch works since it worked before and I didn’t touch it. To test it without this switch I would have to remove it and connect the line and load cable directly. I can try but I fear it’s quite a bit of work for not much gain.

And there is no difference between remote and local switching. Both behave the same way. The blue light switches, I hear a little click, and the light doesn’t turn on.

Referring to the blue light you mean the indicator LED, right? That is a fixed color. (You can change it but once you do it will stay that color.) It should not change colors just because you turn the switch on an off.

I don’t know what would cause a switch’s LED to change colors with an on or off press. I’m guessing it’s either your switch or your wiring is not correct.

If you mean that the LED changes intensity but remains the same color, then disregard this.

Sorry. Bad English on my side. It doesn’t change the color. It’s changing intensity.

No problem. So this worked properly when you first installed it and after a bit of time it stopped working? In between the time it was first installed and the time when it stopped working did you change any settings or flash firmware? If so, what did you change or what did you flash? Or were there any other changes that could conceivably have affected the switches operation?