This API endpoint is used to retrieve a secure access token, which is essential for authenticating and authorizing all subsequent API requests. The process follows a client credentials flow, where the merchant provides their unique merchant ID and x-api-key to securely exchange for a valid access token. The access token grants temporary access to protected resources and is valid for a period of 2 days. After the token expires, a new refresh token request must be made using the expired access token to obtain a fresh one. This ensures that long-term sessions remain secure and access control remains tightly managed. ⚠️ Note: Attempting to access protected endpoints with an expired token will result in an authentication failure. Always check token validity before making API calls and refresh proactively.