How do I add custom fields to a post?

Please check out the documentation linked below, and let us know if you still have any difficulty.

Good luck!

Assign custom fields

I managed to sort it by adding this to the functions.php file:

add_filter('acf/settings/remove_wp_meta_box', '__return_false');

Well, you never mentioned using the Advanced Custom Fields plugin ??

Glad you got it resolved though.

Good luck!

I wasn’t using it at the time, but figured that may work