Thank you for writing back and I am very sorry about your issues. Unfortunately, it appears now that this is a physical or mechanical problem of your external hard drive. We cannot use any software to recover the data inside it, though there are several recovery software out there, since the drive will no longer be detected and initialized by a computer system in its current condition now.
So your only option to recover your valuable data is through Seagate's In-Lab Recovery service. This is the only method that the data in your faulty drive can be recovered using their specialized recovery machines.
To know more about this In Lab Recovery service from Seagate, here is the link:
There are other data recovery companies that can recover your valuable data in that faulty drive besides Seagate which manufactured your faulty drive. The other data recovery provider is Kroll Ontrack and here is their link:
The this one is this link which guarantees no charge when no data is recovered:
I hope that helped.
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