So, looking that the json file you attached
"fields": [
{
"key": "staff-members",
..............
the we look further down at
"sub_fields": [
{
"key": "name",
..............
That is the problem. The plugin that you had installed, the validation field plugin, changed the key value. It should look something like field_0112ab5e75678. This is the reason that data is not saving properly and being retrieved properly by ACF5. This kind of field key renaming used to work and may still work in ACF4 but won’t work in ACF5.
This is what a normal field export would look like:
"fields":[
{
"key":"field_55946dcc88ab8",
..............
You need to delete the entire works and recreate it without that plugin being active and you need to contact the developer of that plugin about making it compatible with ACF5, or at least remove the “or greater” part of where it says “Requires Advanced Custom Fields version 4.0 or greater.”
EDIT:I have been looking for information on when this changed or if there is a setting that will make these fields work, but I cannot find anything. I do remember that in the past at some point I had a serious issue with one of my plugins. It stopped working completely. I was also using custom key values that did not conform to the ‘field_’ pattern. I corrected the problem by making sure that my keys always conformed to this pattern and since then I have not tried to use custom key values.
acf-export-2....json
