Ok I solved it but for anyone else having issues. I just clicked the “Reset” Arrows on the right of the tags in the level editor. and now when I update my tags in the blueprint its working again.
I cant honestly explain how or why? If anyone knows potentially why this happens. Id love to know.
Its like the level editor version took over control of that one specific piece.
This happens when a value at the level - which previously differed from the default - becomes equal to the default value (or something like that). At that point, the actor gets confused about whether to use the value from the Blueprint or the one set at the level.