Transparent PNGs not working on the iOS photos app

Lately, whenever I tried to save a picture from anywhere on my iOS device, it always disables transparency/converts the PNG to a JPEG file. I didn’t have this problem before and it only occurred to me recently. I tried all kinds of workarounds (saving it to iCloud first/sending it to myself per email and saving it from there).

It’s incredibly frustrating. I’d be thankful for any tips and of course of Apple would resolve this issue…