PDF cannot access file

Hello Dev,

I have some problem about showing pdf that when I click on the book sometime it’s shown popup “Error: cannot access file!” so I try debug with inspect on chrome I got message “Uncaught (in promise) TypeError: network error”

after that I try to add Access-Control-Allow-Origin in my .htaccess file like that
<IfModule mod_headers.c>
Header set Access-Control-Allow-Origin “*”
Header set Access-Control-Allow-Headers “Range”
Header set Access-Control-Expose-Headers: “Accept-Ranges, Content-Encoding, Content-Length, Content-Range”
</IfModule>

and clear all cache and re-test again it still hav an error.

Could you please advice me how to resolve this error.

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