Three Echo Dots, same account, but one doesn't recognize smart bulb groups

[scottymo]

Here's a tricky situation. Anyone have any ideas?

- Three Echo Dots in the house
- Two of them recognize the group names I have set up in Philips Hue and Apple Home apps, and I can turn on and adjust group brightness just fine
- One of them (unfortunately, the one that is nearest to the groups in question) does not recognize groups. I can turn devices on and off only using device names. Group names that work on my other two Dots do not work on this one.

I've tried resetting it and setting it up again using instructions from https://www.amazon.com/gp/help/customer/display.html?nodeId=202080910 , but that didn't help.

I can open the Alexa app on my phone, and browser the group and device names, and they match what I have set up in my Philips Hue and Apple Home apps. But for some reason, that one Echo Dot doesn't recognize group names when given voice commands. The other two recognize them just fine.

Funny thing is, all three of them used to recognize group names. But out of the blue, a few weeks ago, one of them stopped working.