Project Label API

My API endpoint, "Project | Add Labels" (POST https://api.companycam.com/v2/projects/{project_id}/labels) returns confusing results. It seems to return JSON of existing Labels and does not actually add the Label I post. Can you please help?

See screen capture:

https://static.companycam.com/lambda/projects/35603471/photos/aHR0cHM6Ly9jb21wYW55Y2FtLXBlbmRpbmcuczMuYW1hem9uYXdzLmNvbS83YzMzMmEwMS05OGI1LTRmYjYtYmE3ZC0wYmE2MjFkMzk5YjcuUE5H.jpeg?d=2880x2880°rade=true