Type Profiles into the Quick Find search bar and select Profiles from the generated results. The Profiles page will open, listing all the profiles active in your Community Site.
Locate your Community’s Customer Community Login User profile using the Customer Community Login license. It should start with your Community’s name. In this example, we are using the Fonteva Customer Community Login User profile.
Click Edit to edit your profile. The Profile Edit page will open. Navigate to the Custom Object Permissions section and uncheck View All and Modify All for all options. Click Save to apply your changes.
Now you’re ready to configure your Sharing Sets for Accounts and Contacts. Follow the directions here.