Sorry to hear and hope you can get it fixed quickly without hassle.
There IS a way to "repair" your lined files... Viewing your processed TIFF at 100% in your editing software, locate the line, select everything to the right of it, and move that selected part leftward 1 pixel to cover the line. I can't tell where the line was, after that. At least this prevents the line from showing up in large prints etc. Good luck!