Canon imageRUNNER 6570 Reference Manual page 491

CAUTION
When closing the top cover of the duplexing unit, be careful not to get your
fingers caught, as this may result in personal injury.
14
Open the lower left cover of the duplexing unit, and remove
any jammed paper, as shown in the illustration.
15
Gently push the duplexing unit back into the machine.
CAUTION
When pushing the duplexing unit back into the machine, be careful not to
get your fingers caught, as this may result in personal injury.
9-19
Clearing Paper Jams
9