My toilet is overflowing when you flush it and even when not using the toilet when I went in the restroom and looked over and noticed the water had rose up to the seat and toilet hadn't been used all night, recently apartment manager had the city come out to snake the system due to everyone in the building had backed up overflowing toilets, and I was told mine is the only one that has called in still complaining. What could be the problem?

Are you on the ground or 1st floor?

when I went in the restroom and looked over and noticed the water had rose up to the seat and toilet hadn't been used all night This tells me that the problem isn't in your toilet but in the building drainage system downstream from your unit.. Since the building drainage's in the common area the repair should be paid by the building owner or the Condo Board. Good luck, Tom