How to save screenshot in-game on ios, and keep it saved after reopening the game?

Hello everyone and sorry for my english! I’m trying to create blueprint, which can save screenshot from camera or pawn camera, while game is running, and save the screenshot to the project folder. It works perfectly on windows, but on ios the game crashes. And I’m sure- the crash is caused by screenshot saving, because without it everything is ok on ios. For this issue I use IpadPro with ios 12.4.1. And I use only blueprint, no c++ at all. Is there any easier way to do it, not with “export render target” ?