I created a Blob today and a duplicate with the same name was made at the same time. I was only charged for one. I didn't notice until I went to make it Hydrus, and the two showed up as twins. I thought it was a glitch until I clicked into my account and saw that I still have two identically named Blobs, one now Hydrus and the other still Common.

I suggest creating a ticket. Staff can probably delete the duplicate for you.

I just made a ticket! Thanks!