I am considering migrating to ACF, but have stumbled upon the following problem:
-> I have a custom field group with multiple fields (Checkbox list, Number fields and so on, nothing too fancy), some of which have default values. However, when I create a new post that uses this field group, none of the custom fields’ values gets saved in the database. When I reopen the post to edit it, all custom fields show again the default values, instead of the actual values that I entered.
The group itself and its fields are saved in wp_posts (having act-field types), but the values of these fields for any concrete post are missing in wp_postmeta.
Am I doing something wrong? I tried duplicating the field group (as some people have suggested here), but it didn’t help.
There isn’t really any way to tell from what you’ve supplied. It could really be many things.
I would start with the basic WP debugging steps. Deactivation of other plugins and changing theme to see if you can figure out is something else is causing it.
My first thought when you say “migrating to ACF” is that you have other fields with the same names as the ACF fields, this could cause the problem.
Another issue could be that you are exceeding the php setting max_input_vars on your server.
All of these are just guesses.