Q: Apple Retail Store rep brought me "storm grey" case when I asked for black, just discovered the difference,what to do?

I had a pick up appointment for my new iPhone 7 plus. The apple sales assistant asked me if I wanted to pick up a case as well. I told her yes, leather black. She walks me to the wall, and picks up what she and I both thought were black Leather.

IVe had it for a week now, and my wife was looking at it and said, " I thought you got a black case"?

sure enough, the case is storm gray. I didn't even know this was an option.

WHat hat can I dp at this point? obviously