Legal Suggestion

I stay in an aprtment comprising of 6 flats at guwahati.my next door flatmate wants to rent out his flat for commercial activity ( garment manufacuturing unit for a butique). as you know the building is a residential property meant for only dwelling purpose as per permission & sale agreement .further if commercial activity is carried out it will lead to serious traffic nuisance because of continous movement of outsiders posing security threat for the inmates & more importantly noise pollution. so seek your legal advice how to stop this . already discussed with concerned person but no response