Have bad breath dentist say my oral hygiene is good and i don't have any cavities. i brush floss use mouthwash dentist are no help i am embarrassed

Halitosis: Bad breath can be caused by many different factors, including sinus infections, periodontal problems, smoking, cavities, acid reflux, and your diet. Address all of these possibilities with your dentist and physician, and I'm confident that your problem will at least be minimized, and hopefully eradicated.

May be indigestion : Bad breath can be related to the food we take ,like Garlic, onion . It can also be related to indigestion ,consult Gastroenterologist to rule out . In the mean time brush your teeth in the morning and before going to bed and scrap your tongue with tongue blade . It is also a good idea to rinse your mouth with antibacterial mouth wash without alcohol before brushing .