Thanks Stu I really appreciate you clearing that up, I will sure keep that in mind. I didn't mean to seem critical, I think the whole website runs like a dream, it just seemed a shame members not knowing the tag goes AWOL, on either side.When a tag is placed during a post edit it will not alert the member. Xenforo only checks for tags on original posts. I'll bet that is what happened in your case. It's quite common, actually and has happened to me on several occasions.
Edit: I just checked morty's post above and your tag was not in the original post. Case solved.
Hopefully this anomaly can become more common awareness.
Hope you are all having a goood night anyhow, thanks again Stu.