"operator does not exist: bigint = bigint[]" Error when I want to use __in lookup agains ArrayAgg field Django

Question

#views.py

queryset = User.objects.all()

queryset = queryset.annotate(
    request_ids=ArrayAgg("requests__id")
)

unread_messages = Request.objects.filter(
    pk__in=OuterRef("request_ids")
)

queryset = queryset.annotate(
    unread_messages=Coalesce(Subquery(unread_messages), 0)
)

I want to achieve something like this in SQL:

WITH user_requests AS (
    SELECT
       uchat_user.username,
       Array_Agg(uchat_request.id) AS request_ids
    FROM uchat_user
    LEFT JOIN uchat_request ON uchat_request.refugee_id = uchat_user.id
    GROUP BY uchat_user.username
)

SELECT 
    *,
    (
       SELECT COUNT(*) FROM uchat_request WHERE uchat_request.id IN (SELECT unnest(user_requests.request_ids))
    ) AS total_requests
FROM user_requests

However I get this error (table might be different but the overall the exception is like this):

operator does not exist: bigint = bigint[]
LINE 1: ...efugee_id" FROM "uchat_request" U0 HAVING U0."id" IN (ARRAY_...
                                                             ^
HINT:  No operator matches the given name and argument types. You might need to add explicit type casts.

Could you please help with that?