With the new (2 years old) serial number layout, you must use the first six characters.
You can see what confusion happens using only the first four by looking at the model-serial table:
https://wiki.mobileread.com/wiki/Kindle_Serial_Numbers
Allow only ONE (1) *.bin file on the Kindle at a time!
Always REMOVE the USB cable before trying to update the Kindle.
(You should never have entered the diags system, and I am guessing that this is how it happened.)
Please provide a screen shot from the Kindle.
(Two finger touch, on diagonally opposite corners of the screen.)