I have one of the original kindles it has frozen I recharged it the light is green, I’ve held the on/off slide for 40 seconds, I’ve left the device for two days but it remains frozen
Sounds like it might be an actual first gen Kindle., Way past likely end of life so it's probably dead. Those have removable batteries if I am not mistaken so you could try removing the battery for a few minutes and see if that helps.
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