Error Implenting Interface

 Hi,
 I'm trying to implement an Interface but I get the following error;

Class 'Blogs' must implement 'Function AddComments(comment As Blog_Comment) As Object' for interface 'IBlogRepository'.   
'AddComments' cannot implement 'AddComments' because there is no matching sub on interface 'IBlogRepository'.   

Models/BlogRepository.vb

Namespace BlogRepository.Models
    Public Class Blogs
        Inherits System.Web.Mvc.Controller
        Implements IBlogRepository
        Private _db As New blogModelDataContext

        Public Sub AddComments(ByVal comment As BComment) Implements IBlogR ...