Using the Add method of an Object inherited from an Objectlist

Question

I have a Tprodutovmi class and to be able to better manipulate the information within a list I created the Tprodutovmilist class that inherits from an Objectlist.

But every time having used the ADD method gives the error of "Access Violation". When I cast an Objectlist for my type Tprodutovmilist I can use it normally, even using its functions, but still the ADD method keeps giving error.

TProdutoVMI = class(TEntity)
   private
      FpurchaseDistribuitionProfile: String;
      FsupplierProductId: String;
      FreceiverFiscalId: String;
      FsubrangeId: String;
      FminSalesQuantity: Integer;
      FtimeUpdateVMI: String;
      FproductId: String;
      FprocessBillingType: String;
      FisControlledByBatch: Boolean;
      FsupplierSalesUnitMeasure: String;
      FuserVMI: String;
      FdateUpdateVMI: String;
      Fstore: String;
      FproductEAN: String;
      FsupplierFiscalId: String;
      procedure SetdateUpdateVMI(const Value: String);
      procedure SetisControlledByBatch(const Value: Boolean);
      procedure SetminSalesQuantity(const Value: Integer);
      procedure SetprocessBillingType(const Value: String);
      procedure SetproductEAN(const Value: String);
      procedure SetproductId(const Value: String);
      procedure SetpurchaseDistribuitionProfile(const Value: String);
      procedure SetreceiverFiscalId(const Value: String);
      procedure Setstore(const Value: String);
      procedure SetsubrangeId(const Value: String);
      procedure SetsupplierFiscalId(const Value: String);
      procedure SetsupplierProductId(const Value: String);
      procedure SetsupplierSalesUnitMeasure(const Value: String);
      procedure SettimeUpdateVMI(const Value: String);
      procedure SetuserVMI(const Value: String);
   published
      property store : String read Fstore write Setstore;
      property supplierFiscalId : String read FsupplierFiscalId write SetsupplierFiscalId;
      property subrangeId : String read FsubrangeId write SetsubrangeId;
      property productId : String read FproductId write SetproductId;
      property productEAN : String read FproductEAN write SetproductEAN;
      property isControlledByBatch : Boolean read FisControlledByBatch write SetisControlledByBatch;
      property supplierProductId : String read FsupplierProductId write SetsupplierProductId;
      property minSalesQuantity : Integer read FminSalesQuantity write SetminSalesQuantity;
      property supplierSalesUnitMeasure : String read FsupplierSalesUnitMeasure write SetsupplierSalesUnitMeasure;
      property receiverFiscalId : String read FreceiverFiscalId write SetreceiverFiscalId;
      property purchaseDistribuitionProfile : String read FpurchaseDistribuitionProfile write SetpurchaseDistribuitionProfile;
      property processBillingType : String read FprocessBillingType write SetprocessBillingType;
      property dateUpdateVMI : String read FdateUpdateVMI write SetdateUpdateVMI;
      property timeUpdateVMI : String read FtimeUpdateVMI write SettimeUpdateVMI;
      property userVMI : String read FuserVMI write SetuserVMI;
   end;

   TProdutoVMIList = class(TObjectList<TProdutoVMI>)
   public
      type
         [Automapping]
         TGroupProdutoVMI = class
         strict private
            FsupplierProductId: String;
            FproductId: String;
            procedure SetproductId(const Value: String);
            procedure SetsupplierProductId(const Value: String);
         public
            property productId : String read FproductId write SetproductId;
            property supplierProductId : String read FsupplierProductId write SetsupplierProductId;
         end;
   strict private
      FGroup: TObjectList<TGroupProdutoVMI>;
      function GetGroup: TObjectList<TGroupProdutoVMI>;
   public
      constructor Create;
      destructor Destroy; override;
      property Group : TObjectList<TGroupProdutoVMI> read GetGroup;
   end;