EXCLUSIVE — Cryptocurrency exchange Coinbase and payment processor Visa are blaming each other for reversed or duplicated cryptocurrency purchases with credit and debit cards, it was reported today.

Today’s news comes after multiple Coinbase customers raised concerns over such transactions and additional fees, prompting Coinbase to respond with this statement claiming “a number of major credit card networks” had changed their codes for bitcoin purchases. Visa, following that statement, released its own which said they were not one of the companies that had done so.

In a series of tweets yesterday, Coinbase shifted away from blaming “a number” of payment companies, and focused exclusively on Visa. The exchange tweeted:

1/ We have determined that the erroneous credit and debit charges are the result of Visa reversing and recharging transactions. This was not done by Coinbase. We are working with Visa to ensure all affected customers are reimbursed.

— Coinbase (@coinbase) February 16, 2018

Coinbase followed that with an additional four tweets (which can be viewed on the exchange’s Twitter here), which stated that “Visa changed the MCC for digital currency purchases to a code that allows large banks and card issuers to charge consumers additional fees.” The company also published a blog post yesterday, which did not single out Visa but instead referred to “the major credit card networks.”

In a statement published on Finextra, Visa refuted Coinbase’s claims, stating that it had not made “any systems changes that would result in the duplicate transactions cardholders are reporting.” This is in keeping with the company’s previous statements on the issue, where it said it had not changed its bitcoin purchase policies.

Visa’s full statement per Finextra reads:

Visa has not made any systems changes that would result in the duplicate transactions cardholders are reporting. We are also not aware of any other merchants who are experiencing this issue. We are reaching out to this merchant’s acquiring financial institution to offer assistance and to ensure cardholders are protected from unauthorized transactions.

Coinbase also noted that it is “actively working with major credit card networks to create a new MCC for digital currency purchases.”

Bank Innovation has reached out to Visa and Coinbase for comment, and will update this story with further news.

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