Help me to deal with chargebacks

HELP ME TO WIN CHARGEBACK ( I AM SELLER) I have sold DOWNLOADABLE PRODUCTS and after one month got chargebacks on few orders, I use 2checkout as payment processor, they ask to provide documentation, please help me to deal with it and win chargeback: 2CO has been notified by the customer’s card issuer that a chargeback has been issued for Sale #105429515279. We have updated the Sale in our system to reflect the dollar amount pulled back by the card issuer. These funds will be recovered from your account and will appear as refunds in your payment details. You have also been assessed a chargeback fee of 50.00 (USD) in accordance with our fee schedule. Reason code entered by issuer of this chargeback, and additional details regarding this chargeback, are as follows: ***CHARGEBACK Details PLEASE DO NOT ATTEMPT TO REFUND THIS ORDER **** 74824874325446688365121 Reason code 83: Fraudulent Transaction - Card Absent Environment - Ecommerce/card not present transaction and customer states this transaction was processed without their permission. To resolve this chargeback: Please provide signed sales draft, website print out, Verisign transaction detail report, or bill to and ship to address. You have 7 days to submit this information to [login to view URL]'s Disputes Department. After the 7 days challenging is no longer an option. The chargeback would need to be resolved with the cardholder directly. If you have any questions or if you would like to challenge this chargeback, please contact us at chargebacks If you have any questions or if you would like to challenge this chargeback, please contact us at chargebacks. Please keep in mind that not all chargebacks can be challenged. If this chargeback allows for a challenge and you chose to do so, you only have 7 days to challenge and you will be assessed an additional fee for challenging a chargeback, regardless of the success in overturning it.