Green Energy Systems - Company not providing service in warranty period

Rooftop solar power plant was installed on ** October **** with zeversolar invertor of * year warranty. It has stopped working and electricity generation har dropped from ** KW per day to ** approximately and sometimes * but green energy system is not providing services and after spending such a large amount we are getting huge electricity bills due to error occurring in invertor. so I am requesting to get into the matter and ask green Energy to solve our problems.