UnauthorizedAccessException: Access to the path

hi guys, this is continuation of my other thread : iOS won't spawn my game Object - Unity Engine - Unity Discussions

after further read the log and i quite sure the thing that cause error and object wont instantiate/spawning on my game is because of this :

its i presume because, when launch, the game will access texture/sprite from secure website using WWW method, with HTTP not HTTPS, and try to download and save it as sprite at Application.PersistentDataPath and then apply it into the game

its working fine on Android but somehow iOS wont allow to read/write the file, hench the error

is there workaround or fix for this?
thank you in advance

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