Western Digital SSD not detected

Western Digital SSD Dashboard version does not detect my WDS200T2B0A. It is my system drive, and my windows 10 operating system boots fine from this drive.

Hmm, seems to be a common theme going here.
I have a WD Black WD500 G2X0C NAND N2VME.
It has worked fine for just over a year, very quick to boot, no issues.
Then suddenly a couple of weeks ago the system crashed after sitting idle for a few hours, it is then unable to reboot.
BIOS prompts to “Select a bootable drive”, and press return, when i try, the message just goes in a loop. This has occurred three or four times now, each time i have been away from my desk so havent seen any error messages.
If i power off and on the system boots normally so the drive is found ok in the BIOS.
I initially Googled this and found numerous post on various web sites of people with the same problem.
Any thoughts?