Why you don't explain it in the owner in coinbase or the support that your site is not a scam or ponzi or any violated site.
Its better to talk the owner in skype and explain it very well.. And i think they can review your site after review and seeing the content inside of your website they will give a review about your site and they explain what rules did you break..
I have repeatedly asked them specifics, like quoting the actual policy change and they wont give me specifics. I have told them that I feel violated for not even been given the exact reason nor even the opportunity to come into compliance with their "recent policy change." All they do is avoid the answering the questions. Not going to waste my time with them. I already had a site review with them once before and they approved of my site, for 2 years. My best guess as to what they have an issue with is that I pay affiliates on 6 levels. Paypal made it a "policy" to not accept mlm way back in their beginning. True mlm is not illegal but PayPal got tired of being the mlm police so they just cut out all mlm. My best guess is Coinbase followed suit. Still pretty damn harsh to just completely close an account without warning nor an opportunity to comply. I can justify closing an account without warning if someone is involved in something illegal, but that certainly was not my case.