Since we all have different symptoms of allergies it might take some time to find a solution for you.
My problems always have been mainly in the head, sinus, ears, brain fog in general and also certain foods. Often in any season.
I remember, as hindsight, that I had it 50 years ago, but never realized that they were allergies.
5 years ago I started liverflushing for Gallstones and after about 8 months I realized my allergies were gone, did not expect this.
Still got foggy feelings but I found that related to certain foods I ate. I changed then to eating according to my Ayurveda bodytype.
Over the years I kept adjusting my lifestyle.