Wordpress Ignorant Tag Issue -

I’ve hit a bit of a stumbling block on my project and just can’t figure it out.

I have a wordpress site with ‘advert’ custom post types.
I’ve created tags and things were moving along fine. One day when tagging the ‘advert custom post types’ wordpress recreated another, almost duplicated, tag.

Original: strong-running-events
Wordpress extra creation: strongrunning-events

Since then I can no longer tag ads into the original, they will only allow to be tagged with the new. I’ve tried deleting the tag, and retagging the advert with the correct original tag, but wordpress just recreates a new one. I’ve tried changing the name but this causes further duplicate tags to be inexplicably created.

Wordpress seems to remember and continues to recreate old deleted tags so perhaps the best course of action is through phpmyadmin?

Could not find a solution for this.
In the end just created a new tag with a vastly different name as a workout.

How interesting just run into the same issue. everything was fine. I was calling a post by a category, simple one like “productivity” & after a while it quit showing up.
wound up having to change the name of the category a bit and now it works.

Furthering this issue…

If you create a tag with commas in the label eg: “strange, unusual, quirky”
Wordpress will create three extra tags for each of these.