Thank you for contacting the support forum.
Before your ticket is assigned to one of my colleagues, please allow me to walk you through some initial debugging steps. This will help speed up the support process.
Yes, the fields are locked if you are not using different fields across the language mode. I assume you are using the same fields across the languages ACFML mode with the WPML translation editor.
In that case, you have to translate the media using WPML media translation plugin. Once you translate the media files those will be automatically translated on the front-end when you update the translation.
