Apple Watch Digital Crown

Unfortunately, you cannot fix the watch. Either pay for an out of warranty replacement or buy a new watch. Those are your only two options.

In that case, you should book a repair.

Apple Watch Service & Repair - Apple Support

If the watch is broken, which it appears it is, and it's not under warranty, you buy a new watch. Apple doesn't fix broken watches. They do offer what is called an Out of Warranty replacement, which is the very same model watch (assuming it's a still supported Apple Watch) for about 60% of the cost of the watch when new. Depending on the model watch, this may not be very wise investment and a brand new watch would be a smarter move.

Diagnostics aren't intelligible to us mere mortals. Apple has machines to read the code. You'll drive yourself crazy trying to decipher diagnostics. Drake211 asked the correct question. You have given us no idea what issue you believe you're having with your digital crown.

Hello,

Could you specify the issue you are having with the Digital Crown?

Thanks for reaching out!

-Drake

What do you mean you got nowhere? When you showed your watch to the Apple Store Genius Bar, the crown worked for them, but won't work for you?