CVS Pharmacy

I made a purchase the other day and 2 days later I was checking my slip and realized they charged me twice for one item. I have been shopping there for 3 yrs. and have all my scripts there and make many purchases consistantly. I told the clerk what happened( this was a 22.00 item) and pointed out the women who had waited on me. She said she knew nothing about it and ignored me, then the clerk called a manager from the back and she looked at me warily and finally consented. They should have been the ones apolgizing for overcharging me, but I felt like I was the culprit. Am having all of my scripts transferred and will never shop there again. This isn't the first issue with this store, lost scripts, etc...