Customer informs us on 5-17 that activity in the amount of $1881 on his debit card (visa)is unauthorized. This is a business account. What is the correct way of handling this dispute? Quite honestly haven't run into a business account before and Reg E is for consumer.

Although Reg E does not cover the business, you are still bound by VISA rules which require provisional credit within 5 business days if the cardholder puts the claim in writing as well as VISA's Zero Liability if you determine that the claim is unauthorized.

VISA Small Business Zero Liability.

Thanks Brian, thats what I thought