WoW wont let me transmog my weapon to my legion weapon and put an enchant on it. When i try it doesnt change and it still makes the noise to when it does. If i also try to transmog other stuff it wont change them either if im doing my weapon to
Here’s the support article for this issue, but also keep in mind it may be a bug with a piece of gear. There have been pieces in the past that cause issues with transmog.
I’d read the article, try the common steps, too: delete cache, disable addons, try transmogging one piece at a time. If all else fails, you could do a full UI reset. But you may find the culprit piece by transmogging one at a time.