Hi there, Robert.
Is that a new drive/laptop or you've been using this drive with the same laptop and this happened suddenly? Can you give a bit more info on what has happened? Do you have data which you need to recover?
You could try the basic troubleshooting steps:
1. Check if the drive is recognized in BIOS/UEFI
2. Try the drive with a different computer either externally (via a SATA to USB adapter, external enclosure or a docking station) or internally via a standard SATA connection.
3. Try updating the drive's firmware if it has an available update and if you manage to get it recognized.
4. Try updating/resetting your BIOS/UEFI, to see if that fixes things up.
5. If you manage to get a computer to recognize the drive, download a diagnostic tool and test it, to see if anything out of the ordinary pops-up.
Hope that helps. Please let me know how everything goes.
Boogieman_WD