Welcome to HCM
I am glad to know that you are diabetic and reduced weight by walking 5 km/day.Please continue the good work.What is your height and weight is it ideal or not(BMI to 22to25) and how much weight you have reduced.Knowing age of patient is equally important.
You are diabetic for >20 years and taking drug suphonyleurea,there is possibility of secondary failure if your diet is also controlled.
typeII why you are not taking metformin?is there any particular reason,if not it may be added after consultation with your Physician/Endocrinologist
Insulin/Gliptin/AGI, are other options for treatment.
You should also check urine albumin,serum creatinine
,HbA1c,and Lipid Profile
A medical check up for effects on heart,kidneys,CNS,Eyes.
Carinitine supplementation may be taken as advised to you it helps to produce energy efficiently from fats,prevents osteoporosis
specially if you are vegetarian in diet.
Good Luck to you