I had the same thing happen to me where I would get a charge for $0.02 every few months from AWS. It was so insignificant that I didn't care to fix it straight away but I was getting concerned that the account might be compromised or the likes. I'm not a regular AWS user so it was actually a huge pain in the ass tracking down what exactly I had to do, compared to more "traditional" hosting platforms. I get that there are safety precautions in place instead of just allowing blowing the entire account away but damn it's annoying.