[DeepSeek Proactively Refunded Users for Data Errors in Its Cache Billing System] According to reports from Zhitong Finance, some developers have indicated that the DeepSeek open platform has automatically refunded the corresponding amounts to API users due to data errors in its cache billing system. Based on notifications received by users, between May 13, 2026, and June 9, 2026, DeepSeek's cache billing system experienced partial errors, which affected the billing of some users' APIs. In response, the DeepSeek team has automatically refunded the corresponding amounts as credits to the accounts of affected users and explicitly stated that API billing deductions will prioritize using the credit account. When both recharge balances and credited balances are present, the system will prioritize deducting from the credited balance. This mechanism ensures that the refunded credits are utilized first in subsequent calls.