Hi, I'm Pete. Welcome to JustAnswer! I'm reviewing your question now, and will post back with your reply ASAP.
If there is a blockage in the paper feed system, the printer will be unable to feed in any fresh paper and will "think" there is no paper in the paper tray.
Did any sheets of paper recently get stuck inside the machine? If so, there may be a small fragment of paper still stuck inside it which is preventing any fresh sheets of paper from getting fed in.
Have a look and check for any obvious blockages or small pieces of paper that may be causing the jam.
If you can't see anything, then try to remove any obstructions by manually pushing a piece of thin stiff card through the machine, where the paper normally goes through.
Let me know if that helps?
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