Welcome to the community, JoanyS!
I'd suggest you check how your WD My Passport external drive appears in
Disk Management. If the external appears to be healthy there, you can try to
change the drive letter assignment. This might actually help you access the contents through My Computer/This PC.
I'd also check how the HDD will appear using a different USB cable and USB port on your computer. In case you have access to another PC/laptop, you might also want to check how it will get recognized there.
If you are unable to see it in Disk Management, you should try
uninstalling and reinstalling the WD My Passport as a device from Device Manager.
Hope this helps. Keep me posted with the troubleshooting!
SuperSoph_WD