On the evening of August 19 (Eastern Time), at approximately 8 PM, ChatGPT experienced a worldwide significant service disruption. This left users unable to log in, register, load chat interfaces, or access past conversations. When users tried to send messages, the system displayed an error message indicating 'too many concurrent requests.' This incident also affected OpenAI's code platform, Codex, and up to 12 API interfaces. OpenAI posted a notice on its official status page, acknowledging login irregularities across all impacted services and confirming that the team is diligently working on fixes. By 8:15 PM that same evening, the incident status had been updated to 'Issue identified, resolution still in progress.'