Unable to authorize access because the client configuration is invalid: invalid_request

I was trying to generate a access token using postman for adobe sign REST api 

I am not sure about i am using correct Acrobat Sign REST endpoint

for example:

https://secure.na4.echosign.com/public/oauth/v2/token 

Callback URL:https://oauth.pstmn.io/v1/browser-callback 

Auth URL: https://secure.na4.adobesign.com/public/oauth/v2 

Access Token URL: https://secure.na4.adobesign.com/public/oauth/v2/token 

Client_Id:SDDDDDDD*****

Client_secret:SDSDFASDFAS***

Scope:user_login:self agreement_read:account

and i click get new access token

i get error like "Unable to authorize access because the client configuration is invalid: invalid_request"