{"error":"access_denied"}

{"error":"access_denied"}

I am trying to generate Access Token using the URL: https://accounts.zoho.in/oauth/v2/token
and sending    {"client_id"}
                 {"client_secret"}
                 {"refresh_token"}
                 {"grant_type"="refresh_token"} in parameters
in the response I am getting {"error":"access_denied"} ans sometimes {"error":"invalid_code"}
Even if I am trying to generate the access token for the first time I am getting these errors for different zoho crm accounts.
Please suggest if I am doing anything or any step wrong. Please guide me.



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