get
https://api.billin.net/v1/contacts
Endpoint to get the list of contacts for the business.
Important limitation:
Swagger UI does not correctly serialize nested query parameters with brackets when using the "Try it out" feature. As a result, requests built through the Swagger interface may not match the expected format and may return incorrect results.
To use advanced filters reliably, construct the URL manually or use an external HTTP client (Postman, curl, etc.).