Carla has worked as a human resources specialist for several years, but she doesn't really like the job. she almost always feels slightly down and sad, which is characteristic of the psychological disorder called

The answer to this question is: persistent depressive disorder

persistent depressive disorder Is a form of psychological distress that is ongoing and happened over time, which make the patient's mood become constantly low most of the time.
This type of disorder often caused by personal dissatisfaction that the person had toward something in their life, either it's job, hobby, or relationship.