I'm migrating from one Zoho books account to another (set in India). I have to do this because the Indian Zoho version is GST compliant. 

I've changed the authtoken, organization id and item codes, etc in my code from the old one to the new one. But I keep getting errors. Whatever I fire, I get internal error code 6.

See this: 

$ curl https://books.zoho.com/api/v3/contacts?organization_id=xxx -H  'Authorization: Zoho-authtoken zzz'

RESPONSE:

{"code":6,"message":"Internal Error"} 

Please help, I need to migrate asap!