Issue Summary

In Jira Service Management Team-Managed Spaces (TMP), the "Create Request Type" API allows the creation of multiple request types associated with the same issueTypeId. This results in data corruption where the Request Types admin page fails to load (HTTP 500) for that particular request type. 

Steps to Reproduce

1. Identify an existing issueTypeId already associated with a request type in a TM Space.

1. Use the JSM Cloud REST API (e.g., POST /rest/servicedeskapi/servicedesk/{serviceDeskId}/requesttype) to create a new request type.

1. In the request body, explicitly provide the same issueTypeId used in step 1.

1. Navigate to the Project Settings > Request Types page in the UI.

There is a 1:1 mapping for issue types and request types in TMSpaces. This is broken when this API is used. 

Expected Results

The API should validate that the issueTypeId is already in use within the TMP project and return a 400 Bad Request or similar error to prevent duplicate mapping.

Actual Results

• The API successfully creates a second request type record with the same issueTypeId.

• The Request Types admin page fails to load with the error: "Something's gone wrong. We couldn't load this request type."

• Internal API calls (e.g., GET /rest/servicedesk/1/servicedesk/{projectId}/request-types) return HTTP 500 Internal Server Error with the message Duplicate key {ID}{}.

• The public API returns both records, but deletion via public API is not supported for TMP projects, leaving the data in a corrupted state.

Workaround

Currently there is no known workaround for this behavior. A workaround will be added here when available