I Have Had Persistent Ear/nose/throat Problems For About 9 Months.

I have had persistent ear/nose/throat problems for about 9 months. I have had strep once in the span of 9 months and always test negative for the rapid strep A test, so they send it to be cultured every time. I have recently tested negative for two strep tests and one mono test, but i frequently have a sore throat, cough, and runny nose/ nasal congestion that doesn't seem to go away with dayquil/nyquil or sudafed.