Photos just turn out completely black. I can't see any traces of the picture I tried to take.

After taking a photo, the film just gets stuck in the camera.

Camera won't turn on, except for the screen, which just displays a blinking E.

It's probably an issue with the shutter. It is probably just stuck in the closed position, which prevents the film from being exposed. If you're taking the picture at night, and there was no flash, then it might be a problem with the motherboard or the capacitor. Contact the manufacturer for a solution.

Check to see if your film roller is still working. Take all the film out and release the shutter. If the film roller moves, then you probably just loaded the film wrong. If it moves only minimally, or not at all, then you will need to contact the manufacturer to replace it.