HomePod Set Up

From the linked article:

Reset HomePod or HomePod mini

1. Unplug HomePod or unplug the power adapter for HomePod mini. Wait 10 seconds, then plug HomePod back in.
2. Wait 10 seconds, then touch your finger to the top of HomePod and hold it there.
3. The white spinning light will turn red. Keep your finger down. 
4. Siri will say that your HomePod is about to reset. When you hear three beeps, you can lift your finger.

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Power cycle your router and check that your iPhone can connect to the Internet via Wi-Fi. Make sure that your Wi-Fi is set up to allow peer-to-peer communications. Try again.

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