Are you eating too much or even any mucus producing foods such as #1 dairy, #2 grains, or in some people #3 fats and oils.
Diff people react to different triggers. Your body is reacting to something it doesn't like. Could even be fumes/smoke/pollution. It can certainly be from your lungs in this case.
Are u asthmatic?
Asthma can and usually is enviro factors including food allergies .
Identify and Eliminate the cause....
Control mucus by brewing 1-2 TB SP fresh whole clove, cinnamon (powder or sticks - good amount), ginger (fresh is better, powder ok but enough to make it hot-ish), tea on the stove in about 1L of water for 10 mins - serve with a healthy amount of honey and lots of lemon. Sip this every day. It's not only delicious, but it clear phlem from all over the body.
You can add turmeric or just have seperate turmeric tea also as much as 3 times a day to clear inflamation.