Gas service

Helloo,myself Joji p v,we have called for help in fixing regulator nd servicing Gas stove on last saturday(mahadev gas service)..The service guy came nd changed the regulator nd fixed new one...This guy named (sunil)came only fix new ones dont know how to clean or resolve the issue...Stove has black smoke coming so he changed the burner which is not suitable for the stove so he cut and altered the burner which is not the exact burner...now the flame is so high not normal nd put a huge amount for the bill(2550) nd told the bill will be send by a guy named (santosh)...nd also promised to change the burner on (monday) but now he is not responding..tried calling multiple times nd even send mail to them which given in google...pls look into this matter ASAP....Thank u.. Service guy num: [protected]