Red wine is another ingredient that strongly attracts flies. All you need is a small amount left at the bottom of the wine bottle to collect the flies. For them, it will be a death trap as they begin to drown in the remaining wine.
Alternatively, you can pour the wine into a container and then cover the glass with perforated plastic wrap.
The last trap is old and used by grandmothers. You need 50 cl of milk, 100 grams of brown sugar, and 50 grams of ground black pepper.
Put pepper, milk, and sugar in a pot and let it simmer slowly for 10 minutes. Then pour the mixture into empty plates and place them around the house.
When flies are attracted to the mixture, they get trapped and drown in the solution. To make it more effective, you can add one or two drops of dish soap to prevent flies from escaping from the surface.
Now, you just need to choose one of these tricks to apply against the flies roaming in your house and see the effectiveness for yourself.