Summary
The request conflicts with the current state of the resource.
When it occurs
Returned for edit conflicts or when a create would violate a uniqueness constraint.
Common causes
- Concurrent edit / lost-update conflict
- Duplicate value on a unique field
- Version mismatch on an update
How to fix
- Refetch the latest state and retry
- Resolve the conflicting change
- Use conditional requests with ETag / If-Match