ERROR_invalid_client in Oauth process

ERROR_invalid_client in Oauth process

Hi there,

I'm tring to create an app for Zoho CRM but I have a problem during the authentication flow.
In the first part of my development I created the OAuth app in the same account that required the permission. The Oauth flow seems correct, after the call I'm able to make call to Zoho CRM with the access token and also able to refresh the token using the refresh token too.
After a lot of tries I moved the OAuth app on a different developer account (recreate the app) and of course I changed all the credential in my code (clientId and clientSecret)

After this operation i'm not able to connect to Zoho Crm through my Oauth App, everytime I'm tried to connect I received a blank page with a simple text: ERROR_invalid_client.

Can you help me? It's possible that this error is because the account is on a different DC ? 

Thanks a lot