I can not connect my HomePod mini. 301009 is the error code. Please help me.

Go through Apple's support document If you can't set up HomePod mini or HomePod to see if you find a solution there.

Is your Wi-Fi set up with WPA/WPA2 and with any guest mode or client isolation feature turned off? Each device on your Wi-Fi network needs to be able to reach every other device for HomePod to configure properly.

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