When you have a cold, flu, or sinus infection, the Eustachian tubes (which connect your middle ear to the back of your throat) can become swollen or clogged with mucus. This prevents pressure from equalizing, causing a feeling of fullness, muffled hearing, or discomfort.
To understand how to fix the blockage, one must understand the mechanics of the ear. how to pop your ears when sick
Try gentle swallowing, yawning, or the Toynbee maneuver first. If those don’t work, a warm compress or steam can help. Never force pressure, and see a doctor if pain or discharge develops. When you have a cold, flu, or sinus