Zoho CRM in Microsoft Power Automate Custom Data Connector

Zoho CRM in Microsoft Power Automate Custom Data Connector

Hello,

I have set up a custom data connector in Microsoft Power Automate. It is a connector to retrieve Zoho CRM data.
I am pretty certain that I have entered the OAuth 2.0 authentication information correctly. However when I test the Get request https://zohoapis.com/crm/v2/leads. I receive a 401 Invalid Token error. 
I have entered the Client ID and the Client Secret.
i have also registered a server base client int he Zoho api console. 
Does anyone  have any insight as to what could be blocking the access token from being used by the Microsoft connector? Has anyone experienced something similar?
I suspect it might be the redirect URI. any thoughts?

Thanks,