The user profile permissions on the Opportunity object is the item that the administrator should
review to find out why the user is unable to delete the duplicate record. The user profile permissions
determine what users can do with records and objects in Salesforce, such as creating, editing,
deleting, viewing, or sharing. In this case, the administrator should check if the user has the Delete
permission on the Opportunity object, which allows them to delete opportunity records that they
own or have access to. If not, the administrator can either grant them this permission or delete the
record for them. Reference:
https://help.salesforce.com/s/articleView?id=sf.admin_general_permissions.htm&type=5
https://help.salesforce.com/s/articleView?id=sf.admin_object_permissions.htm&type=5
