Problem when returning data from Blob fields with TMemoryStream

I'm having trouble dealing with Blob fields. I am using FireDAC with PostgreSQL. The field in the database is of type bytea.

If I create an entity with a mapped property as follows:

[Column('cod_arquivo', [cpRequired, cpNotNull])]
fArquivo: Lazy<TMemoryStream>;

By persisting the information, for example with TSession, the process occurs correctly as the data is stored in the field:

fSession.Save(entity);

But when I try to retrieve the entity, the field comes empty (even the data existing in the database field):

fSession.FindOne<TEntity>(1);

//entity.Arquivo is empty

Here is the complete mapping of the entity:

  [Entity]
  [Table('doc_contrato_documento')]
  [Sequence('seq_cod_id', 1, 1)]
  TContratoDocumento = class(TEntity)
  private
    [AutoGenerated]
    [UniqueConstraint]
    [Column('cod_id', [cpPrimaryKey, cpRequired, cpNotNull])]
    fId: Int64;

    [Column('cod_tipo', [cpRequired, cpNotNull])]
    fTipo: TTipoDocumentoContrato;

    [Column('cod_numero', [cpRequired, cpNotNull])]
    fNumero: string;

    [Column('cod_datahora', [cpRequired, cpNotNull])]
    fDataHora: TDateTime;

    [Column('cod_arquivo', [cpRequired, cpNotNull])]
    fArquivo: Lazy<TMemoryStream>;

    [Column('cod_con_id', [cpRequired, cpNotNull])]
    [ForeignJoinColumn('cod_con_id', 'doc_contrato', 'con_id', [fsOnUpdateCascade, fsOnDeleteCascade])]
    fContratoId: Int64;

    [Column('cod_nome', [cpRequired, cpNotNull], 100)]
    fNome: string;

    [Column('cod_register', [cpRequired, cpNotNull])]
    [RegisterColumn]
    fRegister: TDateTime;

    [Column('cod_change', [cpRequired, cpNotNull])]
    [ChangeColumn]
    fChange: TDateTime;

    [Version('cod_version', 1)]
    fVersion: Int64;

    function GetArquivo: TMemoryStream;
    procedure SetArquivo(const value: TMemoryStream);
  public
    constructor Create;
    destructor Destroy; override;

    property Id: Int64 read fId;
    property ContratoId: Int64 read fContratoId write fContratoId;
    property Tipo: TTipoDocumentoContrato read fTipo write fTipo;
    property Numero: string read fNumero write fNumero;
    property DataHora: TDateTime read fDataHora write fDataHora;
    property Nome: string read fNome write fNome;
    property Arquivo: TMemoryStream read GetArquivo write SetArquivo;

    property Register: TDateTime read fRegister write fRegister;
    property Change: TDateTime read fChange write fChange;
    property Version: Int64 read fVersion;
  end;

{ TContratoDocumento }

constructor TContratoDocumento.Create;
begin
  inherited Create;
  fRegister := Now;
end;

destructor TContratoDocumento.Destroy;
begin
  if fArquivo.IsValueCreated then
    fArquivo.Value.Free;
  inherited Destroy;
end;

function TContratoDocumento.GetArquivo: TMemoryStream;
begin
  if not fArquivo.IsValueCreated then
    fArquivo := TMemoryStream.Create;
  Result := fArquivo;
end;

procedure TContratoDocumento.SetArquivo(const value: TMemoryStream);
begin
  if Assigned(value) then
  begin
    value.Seek(0, TSeekOrigin.soBeginning);
    value.Position := 0;
    GetArquivo.Clear;
    GetArquivo.CopyFrom(value, value.Size);
  end;
end;

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