According to this story, Democratic congressional candidate Gary Wegman’s spot on the Pennsylvania Democratic ballot for U.S. House, 16th story, was rejected because he accidentally submitted a photocopy of his signed declaration of candidacy, instead of the original sheet. He hopes that a state court will reverse the decision and put him on the ballot.
This is a minor technical error that should not disqualify him, and in my experience the courts usually see it that way. Especially since he has the original and can replace the copy at any time.