Bulk imports refresh tokens. This request performs minimal validation and runs batch inserts of refresh tokens with the expectation that each token represents a user that already exists and is registered for the corresponding FusionAuth Application. This is done to increases the insert performance. Therefore, if you encounter an error due to a database key violation, the response will likely offer a generic explanation. If you encounter an error, you may optionally enable additional validation to receive a JSON response body with specific validation errors. This will slow the request down but will allow you to identify the cause of the failure. See the validateDbConstraints request parameter.