Why am i not responding to antiobiotics quick enough? i am already 1 week on antibiotics for sinus infection had it switched and still have symptoms?

Treatment failure: Symptoms of an illness that will respond to a particular antibiotic usually start to improve within 3-4 days if the appropriate antibiotic was prescribed, and they were taken as directed. Relapse or persistence of symptoms is generally regarded as a treatment failure or inaccuracy of the original diagnosis (i.e. viral not bacterial). Decongestants with/without antihistamines may help congestion.