I Am Detected Diabetic 6 Months Back. Iwas Prescribed One

I am detected diabetic 6 months back. Iwas prescribed one Glycomet SR 500 tablet twice a day after food. Since December 2014 I am taking it regularly. Taking no sugar or sweet food and other food as advised. Taking a walk or jogging till I sweat. But sir my BS still remains around 130 in fasting and around 220+ in PP (measured by accucheck last week). Should I change the medicine? Or something wrong in my life style.

Sanjoy Deb Roy
Kokrajhar, Assam