Drive is failing.
It's not gonna get any better the more you tinker with it.
If data is not that important and not worth pro recovery, then at least clone the drive first with non-windows software (e.g. Dd_rescue or Media Tools Pro) and the run GDB on the clone.
But be aware that as the drive is failing, this could cause catastrophic failure at any time, rendering recovery impossible even for a pro.
Any decent pro would have tools and procedures to minimise this risk and maximise chances of recovery.
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