Product: Money transfer, virtual currency, or money service

On XX/XX/XXXX I received an e-mail from Coinbase stating my credit card company two orders that I placed on XX/XX/XXXX for XXXX Bitcoin and XXXX Bitcoin that is worth a total of XXXX USD. I called my XXXX  Credit Card company and was curious why it was reversed when I never initiated a reverse on the purchases to begin with. I was told by XXXX they reversed the orders because I did not respond to their e-mail or text to confirm the orders ( which I never received and have made many other purchases on Coinbase using this same card ). I then called Coinbase on XX/XX/XXXX explaining that the reversal was an accident on credit card companies behalf and that I paid the XXXX USD they wanted due to the reversal. They customer service representative filed a case for me and said I should have immediate access to my account since all they have to do is remove the hold on my account. However, on XX/XX/XXXX I received another e-mail from Coinbase stating my XXXX credit card company reversed another order that was placed on XX/XX/XXXX for XXXX Litecoins ( value XXXX USD ). I logged onto my Coinbase account after receiving that email to gain further information on this order and saw that Coinbase also took XXXX Ethereum and XXXX Bitcoin ( total value XXXX USD ) from me after I paid {$3200.00} USD to gain access to my account 5 days prior. My Coinbase account now said I owe Coinbase XXXX USD in order to gain access to my account including buy/sell/send my cryptocurrency that I have already paid for. I first called my credit card company to ask why another order had been reversed that was made on XX/XX/XXXX and they told me they did not reverse any charge from that day and their must be an error. After getting off the phone with XXXX, I called Coinbase and explained that my credit card company did not reverse the order and that XXXX Ethereum and XXXX Bitcoin ( total value XXXX USD ) was removed from my account by Coinbase to pay for a previous balance I had already paid off on XX/XX/XXXX. The Coinbase representative told me he would remove the hold on my account and attach a ticket to previous complaint so my coins would be returned back to me. On XX/XX/XXXX I received another e-mail from Coinbase stating my credit card company has yet reversed another order that was made on XX/XX/XXXX for XXXX Litecoin ( {$3800.00} USD ) made on my XXXX Card. My credit card company reported no such action was made on the cards end and there must be another error. I logged onto Coinbase and it showed I owed them a total of XXXX USD. 

On XX/XX/XXXX I received another email from Coinbase stating XXXX XXXX reversed an order I made on XX/XX/XXXX for XXXX Bitcoin ( value {$700.00} USD ). I called XX/XX/XXXX and they report they did not initiate any reversal. Then 1 day later on XXXX XXXX I received 1 more email from Coinbase stating my XXXX Card initiated yet another reversal for a purchase made on XX/XX/XXXX for XXXX Litecoin ( XXXX USD ). My credit card reported they yet again did not reverse any order after I had confirmed all these purchases had been made by me. I logged onto my Coinbase account after and say Coinbase took XXXX Ethereum and XXXX Bitcoin from me and shows I now owe them XXXX dollars in order to gain access to my account and XXXX account. 
I called Coinbase and explained my card companies did not initiate any reversals and their must be an error and would like to have my money refunded and coins they took. Coinbase representative said the coins are non-returnable and hung up.