Bajaj Auto — Reduce the millage after free service

Address:

31/1,19th cross st, v.s.puram, shenoy nagat

I have brought my Bajaj 110 on March month.. it was around 60 km per litre. After first free service the milage got down in to 50km took my bike twice where I brought it but till it could not solved my problem..

What should I do for it..

My contact no is [protected]