Nginx custom 403 page not working

Question

Trying to add a custom page for my website, but for whatever reason, no matter what I change it to, it doesn't work. Whenever I change the 404, it works fine.

error_page 403 /blocked.php;
error_page 404 /404.html;
error_page 500 /500.html;
error_page 502 /502.html;
error_page 503 /503.html;
error_page 504 /504.html;

The 403 page always returns the default nginx page regardless of what I change it to.

Answer 1

Try

proxy_intercept_errors on;

Before "error_page" directives: This directive allows nginx to recognize the error code being returned from Apache and run its own directives to display the right page.

Answer 2

Try

error_page 403 = /blocked.php;

Here's the reference