PSA: Ongoing Issues with Coinbase -- Widespread Reports of Duplicate Charges -- Public Acknowledgement by Coinbase
Coinbase-Olga Reddit Post Regarding Multiple Charges
Update as of 9:37 AM PST on February 15, 2018
We are actively investigating some reports from our customers about unexpected credit or debit card charges appearing on their statements from previous Coinbase purchases.
We can confirm that the unexpected charges are originating from our payment processing network, and are related to charges from previous purchases. To the best of our knowledge, these unexpected charges are not permanent and are in the process of being refunded. We are running joint investigations with all parties involved, and will provide updates as we receive them.
We apologize for the trouble, and are working as quickly as possible to help anyone affected by this.
This message seems to clearly state the duplicate charges are the fault of Coinbase's payment network that they likely created theirselves. If you can pause/block your linked cards, it might be wise to do so. However, keep in mind that some customers have reported charges happening weeks after they had removed their card.
Good luck out there and make sure you keep a history of your purchase so you can prove them when you need. And monitor you bank account and when you see a transaction you did not authorize contact them and let them know. They might be able to go ahead and reverse the charge for you.