The drive or enclosure may have failed. Very cheap enclosures are more susceptible to power surges as they are made with no or cheap voltage regulators. This specific device has no switch, and powers up when the computer boots. Though bus powered, or bus automated drives are convenient, there is no separation between the drive and electricity feeding into the unit, potentially putting your drive and the data on it at risk. You may need to ( or have a trained technician ) extract the drive and test it and the enclosure. Hope this helps.
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