Bought this new in 2018. Obviously the warranty is long gone. Over the years I've used it maybe a couple of hundred hours at most - I only use it when traveling. And yet, when I turned it on today it refuses to recognize the hard drive. I have tried everything I can think of:

Running diagnostics, doesn't find the drive at all.
Upgrading BIOS to the latest version.
Downgrading BIOS to the most recent 3 versions prior to the one it used before the upgrade.
Booting from a Windows recovery USB, which can't do anything because there is no hard drive.
Changing BIOS settings to legacy boot, etc. etc. All the things that various youtube videos suggest might help. Didn't make any difference.
Opened the chassis and checked the physical drive connection. It was fine, but I detached it anyway and attached it again to be sure. No difference.

To be completely clear, this is what happens when I turn it on:
Dell logo displays.
Then it boots into the diagnostics by itself, starts the procedure and stops when it discovers there is no drive. Pressing "ok" or "continue" it then shuts down.

The last time I remember it working there were no issues at all.

I have a hard time accepting that just a couple of hundred hours of operation is enough to break a drive. But what can you do..

Question: is there anything at all left for me to try? Could it be something else than the drive? Don't want to invest several hundred dollars in a new drive for nothing.

Any and all suggestions are appreciated.