Django model field different from db field managed=false

[ISMAIL TAIBANI]

I have model containing field ad_account_id = models.TextField(null=True, blank=True) but this model is managed = False and in database type is int and not textfield
whenever i do query using ORM it gives ad_account_id  type as int and not str and don't through any exception as well
why is it so ? and where can i read about this more