Tried henryjamesguest suggestion. Didn't help. Took drive out and put it into my desktop computer and tried to boot from it. Nothing. Tried to read it as an auxiliary drive. Nothing. It must be dead. Is it a coincidence that it died at the exact moment that I updated the BIOS to protect against SPECTRE? I strongly advise others to not update your BIOS with the SPECTRE update.
My computer was an HP laptop. I got the BIOS update from the HP support website. I will buy a good old fashioned HDD to replace it. This was my first and last SSD. I bought my first computer with an HDD in 1985 (10 MB?). I have never had an HDD fail on me except one that was DOA.