Aws problem when using the download api- unity-c#

hi there i want to download through script 3d models and embed them in my app. but for some reason i get this error message :

<?xml version="1.0" encoding="UTF-8"?>

AccessDeniedInvalid date (should be seconds since epoch): 163069475456?

i must say that i using the download link i can download easily from chrome. but from code with the exact same link- i get that error message.

i will glad to get help for that

You need to use our Download API for scripted downloads:

this is what i did