Word/PowerPoint to PDF conversion not displaying shapes

Hi, I have only recently started having this problem (within last two weeks or so) where I create a page in Word or PowerPoint with images and shapes and then when I convert to PDF, some of the shapes are transparent (but not all of them). This has never happened before. I tried converting from Word/PowerPoint to PDF a couple of different ways: From Word/PowerPoint: File>Export>Create Adobe PDF, File>Save as Adobe PDF, File>Print>Adobe PDF and each way the same thing happens in the converted PDF. I also opened a PDF created by someone else that had graphics and only some of them were transparent there as well. I tried seeing if there were any updates available and there were none. I did a repair installation. My version of Adobe is Adobe Acrobat Pro DC version 2021.005.20060