Why do i keep getting kidney infections and uti's after having 2 kidney surgeries and 6 stent placements?

Need more history: U have a complex problem if 6 stents were required. U will always be at risk 4 kidney infections with stent in place. Would consider 2nd opinion from a different urology practice. U have not been "fixed" & possibly have a ureteral stricture or recurrent kidney stones. Will always get recurrent kidney infections unless all stones are eliminated because antibiotics don't eliminate bacteria in stone