I’ve registered an app, and can quite happily generate an access token using the Auth Code Grant Flow. Alongside the access token, we get a refresh token returned - but there’s nothing (that I can find) in the developer documentation that tells us how to go about using the refresh token to generate a new access token. I’ve tried a post to the oauth/token endpoint, with a grant type of refresh_token and all other usual bits of information provided, but get a 401 returned with the following error:
The request is missing a required parameter, includes an unsupported parameter value, or is otherwise malformed.
Does anyone have an example of this working?