The Lead Scoring feature is available at the B2B license. When Lead Scoring is enabled, your administrators will need specific permissions to access the tools in your account, outlined below.
Account admins must have the permission "Lead Scoring" enabled. To review Roles and Permissions, see this help article: How do I create or edit a Role?
There are a couple of ways to accommodate the new permission for account administrators.
A) Create a new role, name the Role Lead Scoring Permission, uncheck all permissions (if there were any) and make sure only Lead Scoring is checked. Save, and you now have a Role specifically for Lead Scoring.
B) Edit an existing role, and add the Lead Scoring permission but checking its appropriate box.
No permissions needed, the feature just has to be enabled on the account.