Defining a CRM User
CRM User allows JIRA-users make issues operations in CRM on behalf of CRM User. This user guaranteed has all required permissions and roles that regular users may not have.
Also some background operations with no logged JIRA user can be made by CRM User. For example during contacts synchronization or issues fields autocomplete, issues update when Company field is updated.
Look here an example:
You could define the CRM user here: