Recurrent uti. Right still getting uti!

So I have recurrent uti for past 9/10 years. It started around 2014/15 till now. Earlier there was every 2to 3 months but now almost in every month. Done with almost every test and everything is o.k. but still having uti. one urologist put me on prophylaxic dose of nitrofurantoin 100 mr for 6 months.I had it for 6 months .I stopped it in Feb 2023 as 6 months completed in April again I have uti. So again I have full course for 14/15 days martifur 100 b.d. and again I took prophylactic dose from July.On December 16 I have completed 6 months so I stopped and I had uti on 9 th Jan . Everytime I got positive for E.coli and sensitive to nitrofurantoin but this time my urine sample comes sterile for culture but in urine routine test in had 60 to 70 pus cells. What should I do. Doing everything right still getting uti