Follow these steps to activate a Duplicate Check license for your sandbox.
You can only create a sandbox license from your production organization.
- Navigate to the DC Setup - View License.
- At 'Sandbox Licenses', click 'Add Sandbox'.
- At 'Sandbox Name', enter a name for your sandbox. Any name is accepted here.
- At 'Organization ID', fill in the Organization ID of your sandbox.
- Click 'Add'. Your sandbox license is now activated.