Constant sinus infections after septoplasty. What's wrong?

Had septoplasmy and turbinate and polyp removal/ reduction, 8months ago. I've had 5sinus infections and constantly congested. Is there something wrong? Never got sinus infections like this before. Had the surgery bc of my deviated septum and I'm a singer. This is way worse then before. Also had my tonsils removed the same time and I've had strep since the surgery.