Hi, thanks for letting us know! That error probably means that someone put the "Vladimir Makarov (CoD)" tag in the fandom field for one of their works, and then a tag wrangler synned it to the Call of Duty fandom tag. It's a pretty annoying problem, but thankfully if you put a different disambiguation, it should work! As an example, "Vladimir Makarov (CoD Video Games)" will probably go through.