post
https://api.campaign.episerver.net/rest//folders//unassign
Unassign a folder to an entity, such as mailing, message template, custom blacklist, image, recipient list or attachment.
The entity was unassigned successfully.
The entity ID is required. Check for the ID of the entity and add it to the request.
The folder could not be found. Ensure that the required parameters such as "folderId" or "entitiyId" are correct and the folder exists.
The folder could not be unassigned from the mailing entity because the entity is a campaign child. Ensure that the entity is not a child of a campaign.
