Coinbase Pro halts BTC/USD trading
Cryptocurrency exchange platform Coinbase announced earlier today that Coinbase Pro had identified a problem in the bitcoin/US dollar (BTC/USD) order book, because of which the pair was temporarily unavailable for trading on the platform.

Coinbase Pro’s problems saw disgruntled users take to Twitter
Coinbase Pro on Twitter announced: “We are currently investigating issues with trading on the BTC-USD order book.” but gave no further details on what had led to the halt in trading.
The Coinbase Global Digital Asset Exchange [GDAX] product is divided between Coinbase Pro and Coinbase Prime. Coinbase Pro mainly focuses on individual traders while Coinbase Prime focuses on institutional investors.
Coinbase Pro order book refers to the current orders on the exchange platforms. Customers buy and sell order for a particular cryptocurrency along with its respective pair. Users can also see the value at which the cryptocurrency is being purchased and sold at real-time.
Problem identified
The exchange platform stated that they identified the problem which was stopping the customers from trading on BTC/USD and were working on solving the issue, adding later that they cleared the BTC/USD in order to solve the issue. The platform further stated that they cleared all the resting orders on the order book and would be in cancel mode until they finish investigating the problem.
Coinbase announced that the BTC/USD order book lacked the sufficient liquidity which was required to enter the limit-only mode. This was the reason for the clearance of the book and the platform is expecting to re-open the book at post-only mode at 4:00 p.m universal time co-ordinated (UTC). The post-only mode is set to remain for a minimum of 10 minutes.
However, several of the exchange’s users took to Twitter to complain that they were unable to cancel their purchase order, leaving them susceptible in the event of an actual hack.