Try removing and adding the PDF again. You can also add a description of the PDF and add it as Other instead of category Sch H (make sure "Form" isn't in the description). I found Form W-AR from page 5 of the Schedule H & H-EZ Instructions that could‌ help as well. 
Here's some other links: 
How to attach PDF files to federal or state electronic filing in ProSeries
Common questions about Schedule H in ProSeries

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