Who has told a buyer that what you have is not what they need?

mopowers said
Similar thing happened to me a while back. How did you handle it? How often did they call you about it?

I instructed him on what to do and it was running in about 15 seconds... LOL. He called a couple more times and if I remember correctly, I kind of reminded him of what I told him before buying it and that he needed to find somebody in his area that could help him understand what he bought