i recently bought a Sharp portable electronic typewriter model PA-3020 II and I've had it for a few days now. its been erasing and typing good, ribbon is still full, but whenever i try to type, it gives me a beep. I started reading the manual it came with to see if there was something that could help me, but there was nothing. I think it has something to do with these left and right margin settings, but i cant figure out how to use them even if i do read the manual 3 million times. i really need help, please get back to me soon.