Hello.
Thank you for asking at HCM.
I went through your history and would like to make you suggestions as follows:
1. I would like to know the type of nose drops you are using on regular basis. This is because they are "decongestant" types of drops, with long term use, they themselves can cause worsening of nose obstruction, which needs another treatment.
2. Blood tests for 
food allergies may not be always reliable. If you have no improvement after avoiding foods, I would suggest you to introduce each avoided food one-by-one every week. If you feel worsening of any symptom with particular food, you may restrict that particular food.
3. Were I treating you, I would suggest you daily 
montelukast and an antihistamine like cetirizine, 
levocetirizine, etc.
4. Daily steam inhalation and 
nasal irrigation with saline also will be helpful.
5. Please avoid exposure to dusts, smokes and air pollution as much as possible.
6. It's great that you are doing 
Yoga, I would encourage regular Yoga & Pranayama under guidance of a qualified person.
7. A healthy diet rich in 
vitamins & minerals (adequate amounts of green leafy vegetables, fruits, sprouts, etc) will also improve your immunity and will be helpful in a long run.
Hope above suggestions will be helpful to you.
Should you have any other query, please feel free to ask at HCM.
Wish you the best of the health.
Thank you & Regards.