403 Forbidden - CURL Request From Server IP

I am facing a problem, I have a file named exec.php, I am executing this file from another PHP file functions.php (On Same Server and Same Server's IP) via CURL and getting response as JSON.
So it works pretty well, after 24 hours or sometimes more file starts showing 403 error. And if i restart the litespeed, 403 error disappears and everything works well again.
But, when i try same file (WHILE IT SHOWS 403 ON CURL REQUEST) from my Local IP it works file.
I have also tried CURL with PROXY, so when IP is changed via PROXY it works fine. When i disable PROXY it shows 403 again.

So i know that litespeed is blocking my own server's IP, but how can i fix that? Where i can whitelist my server's own IP so that no request is blocked?