Getting GUID Value From StoredProcedure.ExecuteScalar()

I need to execute stored procedure which is suppose to return GUID to my IF statement and if it is Nothing I execute other Stored procedures else some other procedures.
My problem is that even though by looking at the data I know that after the execution of the procedure it should return some guid value it doesn't anybody who had the same issue???
 
That is the code block where I am trying to return guid from my stored procedure: 
 
 getGroupID.Parameters("@GroupName").Value = dr.Item("Group ID").ToString()
            If getGroupID.ExecuteScalar() = Nothing Then

                'Find Group by IP address if input Data Table doesn't have group
                getGroupIDByIP.Parameters("@IP").Value = dr.Item("IP").ToString()

                If getGroupIDByIP.ExecuteScalar() = Nothing Then

                    insertGroup.Parameters("@GroupID").Value = Guid.NewGuid
                    insertGroup.Parameters("@Group").Value = dr.Item("Group ID")
                    insertGroup.Parameters("@ACCID").Value = getAccID.ExecuteScalar()
                    insertGroup.ExecuteNonQuery()
                    command.Parameters("@Group_ID").Value = getGroupID.ExecuteScalar()
                Else
                    command.Parameters("@Group_ID").Value = getGroupIDByIP.ExecuteScalar()
                End If
            Else
                command.Parameters("@Group_ID").Value = getGroupID.ExecuteScalar()
            End If
 
Thank you