Two neighbors keep 7 cats to torture me

I am renting an apartment. My floor has three apartments, and mine is located between two others: one with two big cats, and the other with five cats of varying sizes.

The second apartment's balcony is next to mine. Its owner goes to work all day, locking the cats inside but leaving the balcony door open for them to run, jump, and play. I had taken precautions and fenced off the two balconies so their cats couldn't climb over to my side. However, every day when I come home from work, as soon as I open my balcony door, a foul smell blows straight into my room.

To be fair, the owner does clean up when she gets home in the evening, but since I arrive earlier, I have to endure the smell that has accumulated all day. Living in a small apartment, I can't keep the door closed all the time. I need fresh air to feel better, but instead, I end up inhaling all the unpleasant air, which makes me feel sick.

As for the apartment with two cats, it has only one window facing the passage. The owner leaves the window open all day so the cats can run outside and play. On weekends, the girl who rents that apartment goes back to her hometown, leaving the cats behind to fend for themselves. Those times are truly torturous for me.

I do not object to people keeping pets, because that is a personal preference. However, when we live in close quarters, there must be a way to avoid affecting others. Raising pets should not come at the expense of others' comfort.

I have approached my neighbors a few times to advise them on cleaning to reduce the smell, but the odor doesn't disappear immediately. They clean up for a few days, but then it all returns. I am hesitant to keep bringing it up, but honestly, I am raising a small child, and moving is very difficult, so I have to endure this situation.

Hopefully, dog and cat owners will soon improve their awareness so that people around them will not suffer.

Have you encountered similar problems with neighbors who have pets?