In the Jira Service Management board UI, I'm able to create a an issue and assign it an "Issue Type" such as "IT Help".
Example:

However, the rest API endpoint for Jira Service Management that creates customer requests only accepts request types, and not the base issue types.
Is there a way to create with the base issue type through the Jira Service Management REST API? We are trying to support an account with Jira Service Management access but no access to the Jira Cloud rest API.
I have tried sending the "issueTypeId" value for the base type to the create customer request endpoint, but it was not accepted.