When opening the verify view the chart is twice as big as it should be and if the DMC numbers are added you can see the chart picture twice. (Or three times)
This happens if the PDF contains the pattern multiple times. For example one black and white chart and one color chart. Or once with backstitch and once without. If that is the case the easiest way to fix it is to use a PDF editor to create a copy of the chart that only contains the chart once.
For example this online service: ILovePDF