Is there any way to know the date of the last modification of a custom field made with your ACF plugin to the profile of an author?
I would like to know when was the last modification that the author made in his profile and then show it in another field.
ACF does not do this.
In order to do this you’d need to use a different meta field. It could be another ACF field or just a custom field in WP.
If you want to know when each field is changed then you would create an acf/update_value filter https://www.advancedcustomfields.com/resources/acf-update_value/ and in this filter you would set the change date of the other field/meta_value
or, if you want to know when any field was changed the you would do something similar, but instead use acf/save_post action https://www.advancedcustomfields.com/resources/acf-save_post/