Today (October 15) around 8 AM, the Chinese artificial intelligence (AI) platform DeepSeek encountered a major system failure. A significant number of users reported that the website, app, and API interfaces were frequently displaying 'server temporarily unavailable' or 'server busy, please try again later.' For some users, conversations were cut off mid-sentence, prompting widespread complaints on social media. The system was down for nearly 5 hours before DeepSeek officially returned to normal operation. According to China's Red Star News, the official status page of DeepSeek earlier indicated partial interruptions in chat services and DeepSeek V4.1 Flash API services, with a notable decline in webpage and API performance. Subsequent to this, DeepSeek's official response stated that they promptly identified the fault and immediately carried out emergency repairs. As of around 1 PM this afternoon, all DeepSeek services have been fully restored.