[CAN-ON] If someone has "Contingent Worker" as their job title on Microsoft Teams, what does that mean?

Most people, when u hover over their name on Microsoft Teams, have a job title like "Business Analyst" or "Director" or "Software Engineer" or "Operations Manager".

But some people have "Contingent Worker".

In fact, there are multiple with this.

What does that mean? Why don't they have their real job title on Teams? Or is "Contingent Worker" actually their real job title?