I have tried many nasal sprays, but what is really effective is a salt in water solution (slightly salty to taste) and a 10 ml syringe. Simply inject it into each nostril so that the water comes out through the mouth, a couple of times a day. Cleans out all the garbage really well.
Among the medications, Flonase spray is effective, but saltwater is enough most of the time.
It's 0.9% by mass. You can buy it easily in large bottles so you don't need to learn to disinfect and filter your water correctly.
Make sure you’re using sterile water for this. https://en.wikipedia.org/wiki/Naegleria_fowleri?wprov=sfti1
The saline wash is also known as a Neti pot here.