Unmount and Erase

Hallo everyone,
since two days My Passport for Mac cannot be read on my Mac OS X 10.9.5.
If i try to erase or make Partition I get the following message:
Unable to write to the last block of the device.
I googled it and I try with Terminal.app, restart the system cmd+R and Utility Disk but everything didn’t solve it.
Any other solution, tip, idea?
My device is anyway under warranty, could wd change it?
Thanks a lot for helping me!


Sounds like a bad sector issue. Have you tried running first aid on the unit?

Also you can try using a different computer just in case.

I used first aid from Utility Disk and the same message appears, then I tried to plug it in another computer Mac and Windows, but the problem stays.
I launched WD Drive Utilities and tried the check status, but it still doesn’t work.
How could I do now?