Welcome in H.C.M.
In reference to your medical history , your symptoms, treatment you have taken so far and response of treatment, I would like to say that still you are having respiratory tract
infection with eustachian tube dysfunction
leading to blocked ear.
Persistent infection demands thorough examination by ENT doctor to rule out sinusitis
and local pathology of nose & sinuses along with chronic diseases of throat like chronic tonsillitis
. Few basic investigations like-
1- C.T.Scan of paranasal sinuses
2- Culture and sensitivity of phlegm.
3- Blood- CBC, ESR, blood sugar (fasting & post parendial)
Inferences of above investigations and their clinical co-relation will disclose the diagnosis.