Hydroponic Grow System Source

In the past few weeks it hasn't been able to print anything. It's correctly installed, selected, etc. The problem is physical. When you print, the paper moves through the back of the printer, over a spinwheel, and comes out on top of a tray. Beneath this tray there is a small flat object that I think serves to prop the paper up through the spinwheel.

That flat object has fallen off for whatever reason and I don't know how to put it back in. The instructions that came with the printer only tell me how to plug it into the outlet and how to replace ink cartridges. Does anyone understand and can help out? I'd rather not shell out $40-100 on a new one.