SyncTagsWithType creating unwanted tags

[S4lvioni]

Hi! In a certain page, i have a select that allow you to choose previously created tags to sync to that model.
When editing that page, if i remove a tag from that model, thus leaving it empty and saving, the function SyncTagsWithType try to create a new tag in my db, an empty tag, when the desired outcome is to just remove the sync and not create any tag in that case. What i am missing?