Just an added note , and thanks for the comments from others to this issue.
Albeit , i would not suggest this to the OP to do or try himself , but depending on skills ? cost factor ? and data lost.
I have in the past with some success retrieved about 80% of data ...But ! i do not recommend this on sensitive data or data you you cannot afford to lose.
This has mainly been photos , music , docs that customers could do without in the event of unretrievable or just a cost factor.
So if the drive was going to be turfed , binned anyway , i opened the drive and inspected what the causes could be.
Some were board replace and others were reset Arm , others would run 20 min and stop and i would have to start the recovery process once again , powerup and connect , time consuming as it is , some success on files was obtained on recovery.
This would only be a last resort to retrieve some data and save customers some time in regathering the lost data and sorting.
And yes i dont charge them anything for the retrieval , thats a challenge for myself.