Duplicate charge: should I suspect fraud?

Long story short, I just received a chargeback on my bank statement with respect to a small customer purchase.The purchase in question was made on 5/27/12; I typed the amount into my iPhone and received an authorization ID, which I wrote on the invoice.

The customer has requested a chargeback because they claim they were billed twice for the same purchase.

I checked my batch logs carefully and only one charge showed up: the transaction date and the amount and the device ID were correct. When I called the bank's merchant processing folks, they said (after investigating) that the customer saw a second charge on the next day (5/28/12) for the same amount ($42) and same company (Wild Images Florida). But--and this is the curious part--the record listed a different device ID for the transaction.

At the end of the conversation they said to send a copy of the invoice along with a statement that:

I billed the customer only once; and

I do not use any other terminal device.

I have done this. My question here is: Has anyone else had this happen to them?

Replies

Dave Hinde August 7, 2012 at 1:55pm

I have seen duplicate charges on my credit card account several times, but the second charge disappears after a couple days. I've been told that this happens when the systems sends an authorization through, and then a charge. It's suppossed to delete the authorization, but sometimes it hangs around for a few days. That would explain someone seeing the charge the next day and thinking it was duplicate.
- Geoff Coe > Dave Hinde August 7, 2012 at 2:01pm
  
  Thanks Dave...that's what the cust service folks told me too. We'll see how it shakes out
  - Chris Hoyt > Geoff Coe August 8, 2012 at 9:34am
    
    Dave's right.
    
    But sometimes the duplicate isn't reversed, and that's why you must go through your entire statement when you get it each month and compare it with your books. More than once I had a duplicate run on a customer's purchase and the customer didn't notice it, so they were pleasantly surprised when they saw I refunded the duplicate.
    
    I have since changed processors.
Tim Arnold August 6, 2012 at 3:59pm

Are you using the square? If so, from what I heard it is not encrypted so someone could have copied the wireless communication to your merchant processer.

Tim Arnold
- Michael Reimer > Tim Arnold August 7, 2012 at 1:39pm
  
  Tim - you have old and misleading information. The Square is 100% encrypted now, but in the beginning, the part that wasn't encrypted could only be stolen by the person with the device (ie Geoff). The wireless communication was always and still is encrypted.
- Cassius Callender > Tim Arnold August 7, 2012 at 8:02am
  
  Just in case this raises questions...Square is fully encrypted (at least according to their website). https://help.squareup.com/customer/portal/articles/7764-secure-data...
  
  I would contact the company that you are using to process your CC.
  - Geoff Coe > Cassius Callender August 7, 2012 at 9:05am
    
    Thanks, Cassius.
- Geoff Coe > Tim Arnold August 6, 2012 at 4:51pm
  
  Tim, Thanks. No, as I mentioned I typed it in on my iPhone. So maybe my question is: "Are iPhone4 transmissions secure?"
  - Tim Arnold > Geoff Coe August 6, 2012 at 4:58pm
    
    I don't think it is, sounds like you should call apple and find out or the app you used.
    
    Tim Arnold

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