Brush your teeth after each meal. Use dental floss. Brush the tongue carefully. It often has food particles and bacteria, and needs cleaning. Drink more water.
Dehydration often causes bad breath, especially first thing in the morning.
Saliva does not flow during sleep, so no mouth cleaning occurs at night. Other chlorophyll-containing foods are also good for your breath. Take charcoal by mouth. Let them dissolve slowly in the mouth. This will help clean out your system.