The screen of an Apple device shows the Coinbase exchange app.
Users of the exchange launched an online campaign demanding a refund of their losses after a technical problem caused the company to freeze accounts for weeks, potentially locking in large losses for many customers.
In mid-November, a glitch in trading of two cryptocurrencies was caused by technical reasons. Many of the customers are angry with the exchange for locking them out of their accounts and taking their money.
The issue occurred in November when customers were able to buy GYEN, a stable coin that is pegged to the value of one Japanese yen. POWR is a cryptocurrencies designed to be used in energy trading.
The risks to millions of individual investors plunging into lightly regulated new cryptocurrencies markets are highlighted by the dispute. Stable coins, which are marketed as being pegged to outside assets to avoid the huge price volatility of other cryptocurrencies, are not always as stable as their name implies.
According to Chainalysis, gyen was listed on Coinbase for the first time.
The coin was supposed to be targeting the Japanese currency. It jumped to a high of 0.065343, which is 7.5 times higher than the investors thought they were getting.
The transfer activity to Coinbase peaked on the day of Nov. 18 at $122 million. The peak of transfer activity from Coinbase was on Nov. 20, the firm reports.
It is not known how many customers were involved, how many suffered losses, or how many were able to profit from the sudden spike in price. The coin is currently at the intended level.
The company said in an email to some customers that gyen experienced unexpected behavior due to unusual market conditions. This was further complicated and for technical reasons, the trading of gyen was disabled by Coinbase on November 19th.
Customers who traded with gyen up until 19 November may have had issues with their display of transactions due to the fact that the wallet balance accurately reflected the amount traded.
All buys, sells, trades, sends, and receives of POWR and gyen have been temporarily disabled on Coinbase.com and Coinbase Pro while we work to correct this. We apologize for this and are working to make sure that customers can access funds as soon as possible.
The company will publish a post about the November 19 event in the coming weeks. Both POWR and gyen have resumed trading and can now withdraw from their accounts. Our team is working around the clock to restore full trading on the retail app and respond to customer inquiries. At this time, there is no further comment from Coinbase.
Several customers who were reached by CNBC on Tuesday said their holdings on the exchange were still frozen.
Chris Fleming, the owner of a construction and maintenance company in Ohio, said he bought GYEN for $1,763 on the night of November 18. He said he was shocked when he checked his account.
The coin went up to $151,309 in my account. Everyone would say holy s---. He said that he thought he needed to get his out of here immediately.
Fleming started an online petition, which has attracted more than 1,100 signatures, because he still hasn't gotten access to his funds.
They held my money for two weeks. Fleming said that he could have invested in other coins. They need to give some answers and they need to give refunds to everyone who lost money.
Ricky Peacock is a mortgage lender in Florida. He lost $132,000 after buying gyen at various price points and was locked out of his account. He said his account did not show an inflated value.
Peacock said that after they realized they had made a mistake, they locked everyone else up. My real investment was my investment.
He said that his loss was caused by the lock out of all the users by Coinbase. Customers like myself were thrown under the bus by the company.
Ryan Huett, an Oregon winemaker, is administering a group of more than 1,700 disgruntled Coinbase customers who are looking for answers.
Huett said he bought about $75,000 worth of gyen on Nov. 18 and 19 but his balance was 100 times more than he had purchased. He said he can't trade or transfer his gyen balance of $67,000.
He said that the base should give refunds to people who invested above the stable coin price.
He said that customers who made a lot of money by transferring their money to another platform before their accounts were frozen don't deserve to keep their money.
I equate that to walking into a bank with a $100 check and getting $100,000 for it. Huett said he didn't think you were entitled to that.
Philip Kleinman, a New York City public school teacher, told CNBC that once the company froze their accounts, they couldn't access funds or get help from customer service.
Kleinman said he tried to call the support line, but it took him nearly three hours to give up. He said he needs access to the money he invested.
Kleinman said that they all feel left in the dark.
Lucas Bauer, an Army captain and physician's assistant, said his investment was small but he was angry.
He said that they did not make a stable coin during the investment process. The price went up when everyone got this one digital asset. They took everyone's money, and let its prices increase, and then assumed everyone bought it at that point, and stripped everyone of their money.
He compared it to ordering food.
You put your card information in. You can get two pizzas for $19.88. The pizzas will be for $19.88. All orders regarding pizzas are frozen by the company. The price went up because so many people were ordering pizzas at the same time.
Four weeks later, when they try to fix the receipts, instead of the two pizzas you ordered for $19.88, you get four slices of one pizza, because they are keeping the rest.
Email tips to investigations@cnbc.com.
CNBC contributors contributed to the report.
