Parameter [prompt] value is invalid

I am attempting integrate a program with Authorization Code Flow using cURL; I use Coldfusion, so I have adapted my code based the documentation, but you should be able to understand the URL variables that I am passing:

<cfhttp

method="get"

url="https://platform.devtest.ringcentral.com/restapi/oauth/authorize";

resolveurl="yes"

getasbinary="never"

>

<cfhttpparam type="header" name="content-type" value="application/x-www-form-urlencoded">

<cfhttpparam type="url" name="response_type" value="code">

<cfhttpparam type="url" name="client_id" value="#client_id#">

<cfhttpparam type="url" name="redirect_uri" value="#redirect_uri#">

<cfhttpparam type="url" name="state" value="#state#">

<cfhttpparam type="url" name="prompt" value="login">

</cfhttp>

When I execute the code, it processes and displays code that can only execute if the redirect_uri is executed, therefore, the Ringcentral server is forwarding to the redirect_uri.

Here's what my server finds the following variables on dumping variables off of the redirect_uri page:

error: invalid_request

error_description: Parameter [prompt] value is invalid

state : ydcm2ud3d2edvLde911nvev9zwvhLiLztzkhh4qmyc6beg44se

1) The only variable that is passed to my redirect_uri page is "state"

2) The error does not make sense. The prompt variable value is correct. The documentation says use "login".

I am trying to a response so I can get access token and refresh tokens so I can interact with the API calls.

Please advise....