i-SENSYS MF8550Cdn does not take paper from the multi-purpose tray.

I have a i-SENSYS MF8550Cdn in the office which does not feed paper from themultipurpose tray. If I attempt to use this tray the printer thinks there is a jam. There is no jam as far as I can tell loking under the printer and dropping down the tray above the draw.

Does anyone know what the rpoblem could be and whether ot not I can fix it?

Help appreciated.

Thanks