CMS Category once deleted unable to add again

Hi Web flow community,
I have tried to use the categories under CMS.
I first used it with default elements then deleted that category collection and now trying to create a new category collection custom to what I am building.
Unfortunately I cannot add a new category collection, the old one even though deleted prevents me from doing it.
Here are screen shot of my steps.
Colud not delete existing category collection Deleting existing categories Existing catagories collectin deleted First step trying to add catgories Had to exit without saving the new collection


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