I am having an issue with saving a chart as a PDF. When I right-click, select save as picture, and save the file as a PDF, the PDF that is exported will not open in any program and I get error messages saying that the file is broken (I have tried opening in Preview, Acrobat, Illustrator, Chrome, Safari, and Edge). I have used this procedure countless times and this is the first time I've had this issue. All other files types from this menu work fine, so it is just the PDF causing a problem. I'm running Excel 16.38 on Mac OS Catalina 10.15.5.