OAuth2 connection platform.sh

I’d like to connect to platform.sh API. Unfortunately i fail with authentication already. There is no prebuilt module, so i need to go with HTTP module. What is did so far:

Response is:

error: invalid_request
error_description: The request is missing a required parameter, includes an invalid parameter value, includes a parameter more than once, or is otherwise malformed. Client credentials missing or malformed in both HTTP Authorization header and HTTP POST body.

Sources are Platform.sh API Documentation and https://www.make.com/en/help/tutorials/adding-an-oauth-2-0-connection-with-the-client-credentials-grant-type-via-http

This is working for me on a console, how do i translate in make.com?

curl -u platform-api-user: \
    -d 'grant_type=api_token&api_token=API_TOKEN' \
    https://auth.api.platform.sh/oauth2/token

Thank you in advance.

Best Daniel