That's good to hear!

Maybe a cleaning operation should be done to your KN's floppy
drive? That may solve the format failure, dusty and dirty heads
can be the problem.
The easy way are to buy a cleaning diskette set at your local
PC shop and run it, the hard way are to open the drive and
clean the read/write head manually.
If so, be very careful, gently use a soft cotton-pin and cleaning
licuid such as technical alcohol etc.

Also you could try a factory reset just as a test to see if it is
a "bug" who might disapear by the reset.

Enjoy the music.
Happy Playing.
GJ