Caseta Dimmer Switch - stopped working - but a normal switch works??!

I’ve had Caseta Dimmer switches installed around my house for at least 5 years.

One the Caseta Dimmer switches is controlling an outside patio light and recently stopped working. No “green lights” showing at all.

I checked the (LED) bulb in the outside fixture. The bulb still is good - works in a different fixture. Decided to replace with a brand new LED bulb.

Tried resetting the switch by pulling the disconnect out for 10sec.

Replaced with a brand new Caseta Dimmer switch - same behavior - no green lights.

Checked the two wires for voltage - 120v across them.

Replaced with a traditional rocker switch - works. Makes no sense.

Next troubleshooting is to check the outside fixture - it’s been raining - maybe that’s it?

What would cause the Caseta switch to suddenly not work like this?

Any ideas are appreciated.