Mavenchic — keratin services

I have used keratin service from mavenchic, this company promise you 6 month guarantee about keratin service. After washing my hair for the first time i realized that, there is no changes before and after the service. When i tried to complaint about it. They stopped receiving my complaint. Then i had to visit their office (Fyi... They have not mentioned there address on the website) which is in powai, lodha building. They have call center kind of set up over there, basically to fool people. Owner or whoever lady was seating in the cabin i tried to talk to her, she was not even ready to talk to me. This is how they are cheating people by selling fraud service. Please advice how to stop such people running these kind of fraud companies.