There was a point that I was working for a company called Blizzard, sometimes we got something we would call a high maintenance customer. We had one such case with a high maintenance customer where they stated to usually pretty much ignore the customer in a way. The customer stated that he didn't receive a product. I told my manager, my manager said that it was impossible, the automated system gave him the product. I further investigated it just for my own, just to reassure myself and seeing that he didn't receive it. So I had to go above my manager and we ended up giving the customer the product that they missed out on.