Pixelink Studio

@girlieworks: Yes, i did and still didn’t work. Any .php file should i change?

@girlieworks: I have few plugins but nothing like ACF (Advanced Custom Fields). I inspect on the browser, there is no custom fields coding of whatsoever.
I had tried to re-install WordPress but still not working.

@girlieworks: this option missing from ‘Screen option’ both on Post and Page. You know usually wordpress has screen option that you can tick hide or show on the top right corner. On previous version of WordPress. the custom field option is there, without any plugins to install.