What is the correct way to use OuterRef here?

Question

Django

There is a chat link model:

class ChatRef(models.Model):
    chat = models.ForeignKey(Chat, on_delete=models.CASCADE)
    user = models.ForeignKey(Contact, on_delete=models.CASCADE, related_name='chat_refs')

There is a chat model:

class Chat(models.Model):
    participants = models.ManyToManyField(Contact, related_name='chats')
    messages = models.ManyToManyField(Message, blank=True)
    is_chat = models.BooleanField(default=True)
    creator = models.ForeignKey(Contact, null=True, on_delete=models.DO_NOTHING)
    name = models.CharField(max_length=30, null=True

There is also a view that displays friends. In order for everything to work properly, my front needs a flag to tell if the link to the chat exists. If it does not exist, the front will send a request and it will be created

def get_queryset(self):
        queryset = Contact.objects.exclude(id=self.request.user.id).annotate(
            chat_id=Sum('chats__id', filter=Q(chats__participants=self.request.user))
        ).annotate(
            exists_ref=Exists(Subquery(
                ChatRef.objects.filter(
                    user=self.request.user,
                    chat=Subquery(Chat.objects.get(
                        participants__in=[self.request.user, OuterRef(OuterRef('id'))],
                        is_chat=True
                    ))
                ))
            )
        )

        return queryset.filter(is_active=True)

But this code doesn't work and gives out


How to make this work correctly?