Oauth 2.0 : facing issue to get authorization code

Hi,

I am able to get the authentication code now.

URL I hit from browser (GET call) :-

http://comity.stage.lithium.com/auth/oauth2/authorize?client_id=[url encoded client id]&response_type=code&redirect_uri=comity.stage.lithium.com

I got redirected to another URL, which contains the authentication code :-

http://comity.stage.lithium.com/t5/oauth/comity.stage.lithium.com?code=[url encoded authentication code]&user-id=15&tenant-id=comity

I am not getting expected response for next step.

Step 2 POST /accessToken

poster call :

URL : http://comity.stage.lithium.com/auth/v1/accessToken

example request -

LJdishd:~ joan.doe$ curl -X POST -H "Content-Type: application/json" -H 
"client-id: Fblkh30GinF48502kEsk4FmGslkjdfjasdj=" -d '{"client_id" :"Fblkh30GinF48502kEsk4FmGslkjdfjasdj=",
"client_secret" :"FKDDASDK309slkdfaDkdlkjie92=","grant_type" : "authorization_code",
"redirect_uri" :"http://redirect.example_community.com/getaccessToken",
"code":"i7liaoFaOjG6yDKN4tQYXrhewKog3k4ryYGWLS6hbrI="}' "http://comity.stage.lithium.com/auth/v1/accessToken"

expected response

 { 
    "response": { 
        "status": "success", 
        "message": "OK", 
        "http_code": 200, 
        "data": {
            "access_token": "o5IV0yIiNDj/5lNJ6doJh08LX6SsDwtkDXDVmhGvRtI=", 
            "expires_in": 86400, 
            "lithium_user_id": "2d8c95ed-21dc-4ba6-ab9f-d3eff9c928ce", 
            "refresh_token": "XAAWIWKr38W33SlqYooR9OEJW0um9DoyB/o843rdIxk=",
            "token_type": "bearer" 
        }
    }
}

 actual response I am getting is HTML of my  community home page.

Am I missing anything? Has anyone faced the same issue?

Any pointer are welcome.

Thanks,

Vaishnavi