Hi @Boniz
Can you please explain what you mean by:
‘It disappear both in the Gallery Field metabox and in the “Media modal window” view!’ – what is ‘it’?
Do you have any other fields on the page which are saving to the same field name as your gallery field’s?
perhaps you could try renaming your gallery field to something unique to test this?
Are any other ACF fields saving correctly?
Thanks
E
