Problem with Konica Minolta C203 - P-21 and only a part of image printed on printout

I have problem with a Minolta bizhub C253 MFP. When I print something, only one part of image is printed on paper. Remaining part of the image remains on transfer belt. I changed Transfer belt, but result is same. Also, I saw a couple of magenta lines on printout (in direction of front IDC sensor). I cleaned both IDC sensors, but result is same. The Display show only status notification P-21, and no error codes. Can someone tell me what could be wrong?
Thank You in advance.
Best regards,
Ivan