Matthew Georgiou was having trouble in school.  “He wasn’t listening,” his mother, Melissa, told The Post. “Teachers were saying, ‘Look, he’s a smart kid, he’s just not paying attention in class.’” What first seemed like defiance had a far more troubling explanation — the young Australian simply couldn’t hear. Melissa Georgiou’s son, Matthew (left), saw significant improvements in his hearing after using Earflo for three months. Courtesy of Melissa Giorgio Like his older brother Nicholas, Matthew was struggling with Eustachian tube dysfunction , a condition in which the small passages connecting the back of the throat to the middle ear don’t open properly. When that happens, airflow is blocked and pressure builds in the middle ear, leading to symptoms such as tinnitus , clicking or popping sounds, pain, fluid buildup and hearing loss. Both boys had already undergone surgery to place ear tubes , or “grommets,” in their eardrums to relieve fluid buildup and improve airflow.…