One of the world’s largest and most popular fiat-to-crypto gateways and prominent cryptocurrency exchange, Coinbase, is experiencing a major outage on one of their most traded currency pairs: BTC/USD.

The issue appeared last night shortly after 6PM PT. Bitcoin’s price was frozen and still is frozen at $6,556.25 as of the time of this writing. Roughly an hour later, Coinbase tweeted an update saying they were “currently investigating issues with trading on the BTC-USD order book.”

In response to the issue, Coinbase set the BTC/USD trading pair to “post-only mode” at 11:25PM PT, and cleared all open orders from the order book. Many hours later, Coinbase tweeted another status update identifying the problem, citing a lack of “sufficient liquidity”:

“The BTC-USD order book did not meet sufficient liquidity needed to enter limit-only mode. We have cleared the book and expect to re-open the book in post-only mode at 9:00am PT.”

Coinbase users flocked to popular social media sites like Reddit and Twitter to voice their frustrations. The issue was exacerbated by the fact that shortly after the trading pair was frozen, Bitcoin’s price dropped on other exchanges, causing Coinbase users to panic.

Reddit user u/lendo93 created a thread on r/BitcoinMarkets questioning Coinbase’s “reliability.” Another Reddit user, u/RatRaceConqueror commented:

“I haven't seen anything like this from Coinbase last year except maybe at absolute peak volume. This is really turning me off from them…”

In a response to a Coinbase Pro twitter status update, Twitter user @Hazelpups angrily said:

“Are you saying we can't buy, sell, or set a stop until hopefully 9am best case scenario? So we are subject to whatever the market does and can't do anything about it? And you think this is acceptable? Scumbags.”

Needless to say, Coinbase has upset a lot of its users. For any Coinbase users desperate to exit their current Bitcoin trade, BTC to other crypto trading pairs are still functional. Users are able to trade their BTC into another crypto pair, then trade that crypto pair back into USD.

Coinbase Pro BTC/USD trading is scheduled to resume at 9AM PT.