Ryan Mior

Hi there I am new to this forum but I am a long time Lexus owner. I recently brought my 08 rx350 in with all of these lights on and it was an air fuel sensor. I got it replaced. About two months later, maybe even less, the same lights came in and another air fuel sensor went. Apparently there are two separate ones. I have about 126000 Kilometers on my car. I am wondering if this is a common occurrence and are there any other problems I can expect at this mileage. I already replaced the battery and other than that these two fuel sensors are my other problems.