At 5:21 (UTC+8) on December 15, 2021, the WePiggy-OEC agreement made a short-term error in the CHE oracle, which caused the price of CHE in WePiggy to be much higher than the market price, resulting in abnormal liquidation for users who borrowed CHE assets. Calculated at the price at the time of the incident, the total loss of user assets is approximately US$400,000.