If the paper is thin, it may wrinkle.

If paper is curled, turn over the stack, straighten it and then put it back in the paper tray or the MP tray.

If the paper is not feeding properly, it may be curled. Remove the paper, straighten it and turn over the stack.

When you use the manual duplex function, it is possible that there may be paper jams or poor print quality.

If there is a paper jam, see Paper jams in the User’s Guide. If you have a print quality problem, see Improving the print quality in the User’s Guide.