deducted money from my bank not relevant to servi

I sold my car in September 2015, I informed Tracker they told me that they have already invoiced. how do you receive someone else's money and be unable to run an accounting journal and reverse the receipt and pay back the person their money? what kind of a ******* is that? Tracker is a ******* company and yet there are other tracker companies that we can use out there either than them