Even after holding down both side buttons for more than 10 seconds, my watch is still unresponsive.

what about when none of the things suggested in the Apple Support link work either? Two different charger cables tried - overnight each one; holding both buttons down for more than 10 seconds tried several times. Watch totally unresponsive. What next??

When I go to support to find why Apple Watch will not start, the first thing I am asked for is the serial number of the watch....and am told that the serial number is found by turning on the watch....which I can't do! If I don't enter the serial number, your system will not allow me to get on the online chat.

If your Apple Watch won't charge or it won't turn on - Apple Support

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