Why Is This Child's Cough, Not Responding To Treatment?

A six years young girl, c/o cough from last two months, parents say, it's like whooping cough. Initially, she had a fever for 5days, which eventually subsided, but her coughing continued. The child came to me on 29 March, TLC WAS 25800/_and XRAY showed lower lobe pneumonia Medication: Azithromycin 250mg for five days and cefpodoxime +clavu 75mg bid for ten days, again after ten days cefpodoxime for ten days given, on 26 April TLC 20000/_ and XRAY CHEST similar to previous.

Symptoms did not improve clinically. Rt Lowe chest crept audible, both ant and posteriorly. I s there any foreign body in Rt bronchi,(foreign body pneumonia)or pertussis.