Severe Chronic Halitosis. Issue.

I am a 29 years old female and suffer from severe and chronic halitosis. It started when I was 7 years old and now its been almost 22 years now. I brush twice a day using a flouride toothpaste, scrap my tongue, gargle using hydrogen peroxide after meals, gargle with betadine mouthwash twice a day,drink apple cider vinegar and baking soda in empty stomach twice a day, floss my teeth, perform nasal irrigation (jal neti) using warm salted water twice a day and gargle my throat as well. "I get thick saliva on back of my throat and a white coated tongue everyday". I drink 4 liters of water with lime juice daily. I visited a dentist and he told me that I have no dental problems whatsoever. I got treated for possible stomach issues like H.Pylori and Candida but no relief from bad breath. My doctors confirmed that it is definitely an ENT problem. Please address the possible issue.