In case people are wondering why is this a recurring problem - this simply perils of Market Making in a volatile market. As a market maker for customer orders Coinbase needs to fulfill both sides. So to make money they buy from customers at low price and sell back at a high price. So they are collecting spread between bid and ask to make money.

But what happens if the market moves rapidly in one direction? They end up selling low and buying high.

So, they need to reset the market making algorithm. Or shutdown the site for a "fix", long enough that the volatility comes back in their range.