Has your Echo Dot quit responding? When you plug it in does it respond with a blue, circling ring that just… circles? It could be something as simple as the wall adapter you’re plugging the Echo into. Some wall adapters don’t provide quite enough power for the Echo to function properly. If you’re plugging the cord into another adapter, try plugging it into an original Amazon adapter. One of mine was failing with a TPLink adapter, but it worked fine in a Amazon Kindle adapter.