The source – support.google.com
The call log in Google My Business is an experimental feature currently only available to select businesses in the United States. Here you can see your call history through Google Search and Maps.
When customers contact a company of interest using the call button in their profile, this information is displayed on the Calls tab in their Google My Business account.
The data is stored for 45 days. This allows you to answer missed calls and stay in touch with customers who have found a business on Google. All calls that come through the profile are accompanied by a short message stating that this is a client from Google services.
When you enable call log, you cannot disable automatic messages during a customer call. Text messages are not logged in this log.