Subject: Serial Number Not Found in Apple Database – AirPods Pro 2

Apple's check for warranty coverage on a device by serial number is not a check to determine authenticity. Even if there is warranty coverage showing, it does not mean the device is legitimate as counterfeiters can simply copy the serial number of a legitimate pair of AirPods, and you still would not get any warranty service when it may be needed. For a device purchased from Apple or Authorized Apple Seller that does not show up with any warranty status, it may be necessary to contact Apple directly and submit your original purchase receipt. Apple does not get involved in any third party sales.

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where, exactly, did you buy them?

That doesn't appear to be a valid serial number, which would strongly suggest they are counterfeit.