Flashing yellow light on Alexa device indicates pending notifications or messages
Amazon Echo devices display a flashing yellow ring to alert users of new notifications or messages starting in 2017.

Yellow light meaning explained
A slow burst of yellow light from the Echo ring signals that Alexa has a message to share. This notification system allows the assistant to alert owners about breaking news or calendar reminders. Users can also receive alerts regarding shipped packages through this feature.
How to clear the alert
Owners can remove the flashing light by asking Alexa a question about their notifications or messages. Phrases like What notifications do I have will cause the device to recite the relevant list. Responding to these items as they appear resolves the yellow light issue.
Customizing notification settings
Adjusting Alexa notification settings is necessary for maximizing the functionality of the Echo hardware. The nine different color notifications available provide various ways to grab user attention. Customization helps users take advantage of advanced features like price-drop alerts.
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