Hello there,

There was a security patch update on the 10th of June 2019 to support Client Credentials grant type for OAuth2 (Equinix authentication API), and this may have triggered the problem. Please check if you have passed the correct headers and corresponding values for each grant type.

The Password grant type requires

• user_name
• user_password
• client_id
• client_secret
• grant_type

and the Client Credentials grant type requires

• client_id
• client_secret
• grant_type

For further info refer  https://developer.equinix.com/docs?page=/dev-docs/fabric/getting-started/getting-access-token|requesting-access-and-refresh-tokens

- Equinix Developer Community