Query with Leftjoins using Groupby Includes are not performed EF.Core C#

Question

I need to perform a query with the Entity framework where I have an entity Offer and in it I have several Cards (Entity).

In the query I am performing the card include, and using Selectmany to perform a filter to get only the active offer cards. But when Groupby is performed in the query EF Core is not performing the includes.

Note: As I have two cards in the offer, I need to perform the group by not to repeat the offer, and when I don’t use the group by offer comes with the includes but with the double offer.

Entity (Offer)

public class Oferta : EntityBase
{
    public Oferta()
    {
        Cartoes = new HashSet<OfertaCartao>();     

    }

    public long? OfertaId { get; set; }
    public bool IndicadorSituacao { get; set; }
    public string DescricaoOferta { get; set; }        
    public DateTime DataVigenciaInicial { get; set; }
    public DateTime? DataVigenciaFinal { get; set; }        
    public IdentificacaoEtapaFluxo IdentificacaoPac { get; set; }
    public IdentificacaoSegmentoProspect IdentificacaoSegmentoProspect { get; set; }
    public virtual ICollection<OfertaCartao> Cartoes { get; set; }        

}

Entity (Charter)

public class OfertaCartao : EntityBase
{
    public OfertaCartao()
    {
        OfertaCartaoBeneficios = new HashSet<OfertaCartaoBeneficio>();
    }

    public long CartaoId { get; set; }
    public long? OfertaId { get; set; }
    public virtual Oferta Oferta { get; set; }
    public IdentificacaoEtapaFluxo IdentificacaoPac { get; set; }
    public IdentificacaoSegmentoProspect IdentificacaoSegmentoProspect { get; set; }
    public long? TermoCondicaoId { get; set; }
    public virtual TermoCondicao TermoCondicao { get; set; }
    public string DescricaoCartao { get; set; }
    public string TextoAnuidadeCartao { get; set; }
    public bool IndicadorSituacao { get; set; }
    public DateTime DataVigenciaInicial { get; set; }
    public DateTime? DataVigenciaFinal { get; set; }
    public string IdentificacaoArquivoPoliticaIsencaoDeTarifas { get; set; }        
    public IdentificacaoBandeiraCartao? IdentificacaoBandeiraCartao { get; set; }
    public IdentificacaoModalidadeCartao? IdentificacaoModalidadeCartao { get; set; }
    public virtual ICollection<OfertaCartaoBeneficio> OfertaCartaoBeneficios { get; set; }
}

Query

        var result = _aberturaDeContasContext.Ofertas
            .Include(x => x.Cartoes)                    
            .Where(where)
            .Where(x => x.IndicadorSituacao)
            .WhereInVigencia()
            .SelectMany(sm => sm.Cartoes.Where(w => w.IndicadorSituacao).DefaultIfEmpty(), (key, inner) => key)
            .GroupBy(x => x)                
            .Select(x => x.First());