Love my job....

I have been working in my retail job for about two years now. Most of the time all is well but there are instances every now and then that makes me question how low some people can really be. When I first started as a cashier there was a man who came through my line who was rude, but nothing to really bother me with. We had a promo going that if you spend X amount of dollars you get a free gift card. Well I handed him his card and he walked off only to call back to the store about an hour later saying that I never gave it to him and he was pretty sure I was keeping it for myself. I had to be questioned by security since I was being accused of stealing and we had to watch the tapes and everything. It was horrible but it was clearly shown on tape that I handed it to him and he had laid it down on the counter where the next customer picked it up. Like really!?! What kind of person are you that you would want to get someone fired or potentially arrested all because of your stupidity? Also, to make a complaint about me being super rude! Yea, look in the mirror you were the one making rude comments all the way through the transaction, I kept my cool and tried to stay as friendly as possible. That will change, however, if I see that man return to the store. I can show him what rude is! Don’t make accusations like that about me and think that I’ll forget about it.