Hello We need to evaluate the main reason for the bad breath. There are multiple reasons. Please visit the dentist for scaling that is cleaning of the teeth

Hello Bad breathe all day even after brushing is due to inefficient cleaning. When plaque still remains in the mouth (inability of the brush to clean effectively) you ll persistently feel the breathe. Also mention is there a particular kind of smell(musty,fishy, fruity or ammonia like) ?

Halitosis/bad breath is commonly due to plaque accumulation, tongue coating, gingivitis/periodontitis, or dental caries; also consider xerostomia and GI causes. strict oral hygiene—brushing twice daily, interdental cleaning, and tongue scraping, along with adequate hydration and diet control. Use Colgate Plax or Listerine Total Care mouth wash for maintenance If persistent, recommend dental evaluation (online/offline) for scaling, caries assessment, and to rule out periodontal or systemic causes.

You should visit  dentist to check calculus which producing bad breath.. without scaling it won't subside with home care only

need to examin the oral cavity condition 1st , bad breath may also reason from ur digestive functions

1. Tongue Cleaning (Most Important) 70% bad breath comes from tongue bacteria Use tongue cleaner every morning 2. Warm Salt Water Rinse 1 glass warm water + ½ tsp salt Gargle for 30 seconds Reduces bacteria & gum infection 3. Clove (Instant Relief) Keep 1 clove in mouth and chew slowly Natural antibacterial & fresh breath Studies show cloves help reduce oral bacteria and bad breath 4. Drink More Water Dry mouth = more bad breath Drink water every 2–3 hours 5. Natural Fresheners Fennel seeds (saunf) Cardamom (elaichi) Mint leaves 6. Brush Twice Daily (Very Important) Morning + before sleeping