Hey ,
You can try this. I usually recommend my clients 2x 1000mg D-mannose per day to counter an existing infection. If my clients are dealing with frequent infections I usually recommend them to take 1000 mg of D-mannose per day as a way of prevention.
If you are going to use Uva Ursi as well, it is not for everyone. It is not for kids or for individuals with liver disease. It also works better if the urine is at a lower pH. Avoiding soda, coffee, black tea, cow dairy foods (especially cheese), and too much animal protein, and grains will help lower the pH of the urine.
Vitamin C in the supplement of ascorbic acid will make the urine more acidic as well, so if you are using Uva Ursi it would be helpful to stop this supplement temporarily as well. Of course, vitamin C from foods is not a problem.
Good luck!