Drop Shadow bug in Indesign when exporting as png

Every time I export a png it makes the drop shadow look larger and further away. If I export as jpeg, it is normal. Even with old files where it used to export fine as pngs. It is driving me nuts!!! The only time it works is if I export as 300dpi, but I would like to export as 72dpi because they are sized for the web. This is happening with ALL of my InDesign files. There is nothing strange with them. They are not rotated. They don’t have global settings. They look fine on screen. This has been happening since around the beginning of the year and I have just been avoiding drop shadows hoping it would be fixed by now!! I am on a MacBook Pro 32GB memory, Apple M2 Pro and am using Adobe InDesign 21.2. I have uninstalled and reinstalled InDesign and no luck.