Unable to delete request type associated with email requests.

Summary

Deleting a request type associated with email requests hangs if the issue type is not associated to the project. No error message is shown on the user interface, which would be helpful.

Environment:

JIRA Service Desk Application v3.3.0-OD-1000.796.0

Steps to Reproduce

1. Create a request type. E.g: Customer Questions. Associate the request type with "IT Help Issue type."
2. Enable email requests and use "Customer Questions" as the request type.
3. Go tho the issue type scheme and remove "IT Help" from the project context.
4. Back on the "Request Types" screen, try deleting "Customer Questions".

Expected Results

Customer Questions request type is deleted

Actual Results

The deletion pop up just hangs on a spinning wheel.

The following appears on the browser console:

{"errors":[{"errorMessage":"This request type is the default request type for the email channel."}],"reasonKey":"sd.admin.request.type.error.used.by.email.settings","reasonCode":"400"}

Notes

Related bug: https://jira.atlassian.com/browse/JSD-4097

Having an error on the UI would be helpful as well.

Workaround

Associate the issue type to the issue type scheme.