Another plea here... just in case it's not clear... please ONLY USE RAT POISON IN BAIT STATIONS. Don't use open ones like you see for mouse poison. Dogs and cats WILL eat rat poison left outside a bait station, I've lost cats and my neighbour lost his dog, so please use proper stations.
Also, be very consistent and diligent with your bait stations. It's worse than useless to fill them once and forget them. Believe it or not, rats become tolerant to poison. They need big doses and they need to die, not recover. Sorry to sound brutal. Check bait stations once a day and refill as necessary. If no bait is taken repeatedly, move the station to a better location if you still have problems or empty and store them. Sorry, I know that's all common sense! The problem with common sense is... well you know the rest