To configure which fields are editable in the Create Issue dialog, do the following as OTRS administrator:

1. In the OTRS dashboard, select the Admin tab.
2. In the Admin tab, select SysConfig in the "System Administrattion" section.
   
   The "SysConfig" dialog appears.
   
3. In the "Actions" section, search for jira.
   The search results are displayed on the right.
   

4. Select Core in the list of search results.
   The following dialog is displayed.
   

5. Select Yes for "JIRA::ShowDialog" to display the "Create Issue" dialog.
6. Click Update to activate your changes.