Bad codes for knock sensor

What is your question?

I had a code for a knock sensor come up on my 2006 Chevrolet avalanche so I decided to change it and figured I will just do both while in there so I did both the same brand also put a new wire on and now I have a code say that both sensor's ate giving a low output

How long has your 2006 Chevrolet Avalanche 1500 had this problem?

Since I bought it