Connected Electron won't publish or respond to ping

I have a new Electron Asset Tracker. It’s breathing cyan, and I can see it take new firmware, but I can’t ping it, and it doesn’t publish to Signal MQTT. It was working fine until last night, so I flashed an earlier version of my code that I know also worked, but got the same result. I have an active GPS antenna, a rubber duck telecom antenna, regulated 12V power supply with the battery. The GPS signal is good and the unit is receiving. Why did it just stop responding?

Do you use a 3rd party sim?

No. I’m using the sim that came with it from Particle.

This one is running 0.6.4. I have another one that’s working great with 0.6.2. I’ve compiled the code for 0.6.4 and flashed it successfully both OTA and hard connected.