I am not able to authenticate my Google AdWords account during integration with Zoho CRM. Why?

I am not able to authenticate my Google AdWords account during integration with Zoho CRM. Why?

Only a Google AdWords account with administrator access can be integrated with Zoho CRM. Other accounts with more limited privileges will not be authenticated for integration.​

There are four types of Account Access levels. They are Email-only, Read-only, Standard and Administrative access levels. To know more about Google AdWords Account Access levels and how to grant or remove them, follow this link.

How to grant or remove access to your AdWords account