How do I create a MS Visio drawing, save as a pdf, then create a Stamp, then apply the stamp to a existing pdf

In the past using a Dell PC with Windows 10, I have used MS Visio 2013, and Adobe Pro 10 and was successful in I could create a symbol in Visio, save it as a pdf , save it as Stamp, then apply the stamp to existing (editable) pdf document. However, since upgrading my Dell PC (10/2016), still using MS Windows 10, it was necessary for MS to upgrade my MS Visio to 2016. I now have an issue that causes my Symbols to also show the page outline of new and old drawings I created

in Visio. I was able to first save some new drawings, first as a Word Doc (Changes drawing attributes), then save it in pdf without the page border lines showing.

What gives?