No question that Reg E is as consumer friendly as they come, but before I jump to the conclusion saying the claim should have been approved there are a couple of questions I would want answered.
1. Were the time stamps on the transactions identical? If not, probably not a duplicate transaction.
2. Were the transactions posted on a Monday? I receive a lot of false duplicate charge disputes because the customer bought a pack of cigarrettes on Saturday, and another on Sunday, and although both charges posted to the account the same day and for the same amount, they were clearly two seperate transactions. (I document these dates/times when I deny a claim should it be questioned later and the transaction history is no longer available.)
Also remember that Reg E does allow you to use account history as part of the investigation. If it appears that the customer has a history of making purchases for around this amount and you can determine that the transactions weren't one right after another indicating a true duplicate, you may be within your rights to deny a claim.
Unlike a court of law, a Reg E investigation does not require "proof beyound a reasonable doubt." It simply requires that an investigation be conducted and based on the available evidence, a decision made.
All of that being said, I agree with AFaquir, the bank's ability to receover funds via chargeback has no bearing on whether or not to approve or deny a Reg E claim.
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