Repairing a Canon CS10 Typewriter?

I have a Canon CS10 electric typewriter. I starts OK, but when I type any of the buttons, the typewriter hangs it self up repeating that letter until another letter is depressed.

I'm quite technical. Does anyone know what the problem can be and can help me with tips on solving my problem?

Despite modern ages and having a lot of computers, laptops, etc. in use by me, I have a typewriter located at both my flat and at my office premises which often come in very handy indeed!

The Canon CS10 I have, which I thought would last for a long time, hence bought a lot of accessories for it.

I would be very grateful for any tips on how to solve this problem.