Control which online services an account can be used to access
Some types of online account providers allow you to access several services with the same user account. For example, Google accounts provide access to calendar, email, and contacts. You may want to use your account for some services, but not others. For example, you may want to use your Google account for email but not calendar if you have a different online account that you use for calendar.
You can disable some of the services that are provided by each online account:
Open the Activities overview and start typing Online Accounts.
Click on Online Accounts to open the panel.
Select the account which you want to change from the list on the right.
A list of services that are available with this account will be shown under Use for. See to see which applications access which services.
Switch off any of the services that you do not want to use.
Once a service has been disabled for an account, applications on your computer will not be able to use the account to connect to that service any more.
To turn on a service that you disabled, just go back to the Online Accounts panel and switch it on.