You’re experiencing a known state synchronization issue between Operate and Zeebe where instances appear ACTIVE in Operate but return NOT_FOUND when trying to cancel them via REST API. I found the following relevant resources:
- Operate ↔ Zeebe State Desynchronization troubleshooting guide
- Forum discussion on inconsistent data between Operate and Zeebe
- Migration issues from 8.7 to 8.8
- Vector Database connector documentation - note that Anthropic is not supported as an embedding provider, only as an AI Agent
- Inbound connector deduplication behavior across versions
Does this help? If not, can anyone from the community jump in? 
Hints: Use the Ask AI feature in Camunda’s documentation to chat with AI and get fast help. Report bugs and features in Camuda’s GitHub issue tracker. Trust the process. 