I’m warning anyone who needs merchants accounts to process credit cards NOT to use Card Service International, which I once was very high on. One of their terminals broke and they sent me a new one. The new one, after weeks of attempted programming, was finally found to be defective. They sent me another. This one worked.
However, they never acknowledged my return of the defective terminal and proceeded to charge me for two terminals. The customer service people (who were habitually awful when there were technical problems, hence, the poor programming) refused to listen, and three certified letters to the president failed to draw a response. The only way to stop them from double charging was to change my credit card processor altogether, which I did, and found even better rates at my commercial bank.
Credit Card International now duns me for payment of $95 (!) and will not listen to reason or respond to any communications. They claim I possessed and was using two terminals!
Anyone can make a mistake, but companies that refuse to listen and treat their customers like criminals don’t deserve anyone’s business. I strongly recommend that you don’t go near these people and, if you have an account with them, go elsewhere. You’ll probably find better rates and avoid future unpleasantness.