Sunny, I'm assuming you have taken lots of antibiotics for sinus infections over the years? I'd be really surprised if you hadn't.
My son went through this from a young age, had the tonsils, addenoids removed, had the sinus scraping, the septum repair etc. by the time he was 4 yrs. None of it worked.
I will tell you what worked for us. We had already had him allergy tested and didn't come up with anything really bad, so this wasn't a cause. My mother had been reading up on yeast infections and things that trigger and help them grow, so I kind of implemented some of the steps and it has been a great success for us.
My son's breath was always kind of sour, almost vinegary, or smelled like snot when he was really bad. So this was a gross side effect also.
I cut out dairy products. All of them. I limited all sugary or starchy foods~yeast/fungus loves sugar and will actually cause a host to crave sugars in order to feed it's growth. I started giving him olive leaf extract, a capsule form herbal, that is known to help control fungus growth. We started using raw honey for sweetener, which is also a good antifungal agent.
This was all a resounding success for him! Now he is a teen and we have not had to give him antibiotics since he was 5 years old. When he even starts to get a runny nose or post-nasal drainage, I review his diet. He still craves starches and sugars but we know how to curb the sinus swelling and inflammation now and we just stop letting him eat them, go on the olive leaf extract for about 3 days, and are still amazed at how effective this is.
Olive leaf extract is not costly and cutting out dairy and other processed foods is a money saver also. Raw honey can get pricey but it's worth it's weight in gold.
This is a good thing to try if you don't have money for surgery and you want to take an active part in your own health.