Suggest Remedy To Produce Maximum Milk To Breastfeed

When my baby was of 3 months, his apetitte increased, and I used to produce a lot of breast feed that it would leak but after his 3 month nor did his apetitte was satisfied nor my milk would leak, I wanted him to feed my milk for at least a year. My mother in law introduced Lactogen to him saying that I don't produce enough for him. Giving him formula he got so used to it that he refuses my breastfeed even if I want to give him and obviously biologically, I stopped producing enough.

He is of 5 months now, going to be of 6 months on the 11th of October. I don't want to give up my breastfeed. Please help me. Suggest me anything to produce maximum milk. I tried all what the people say, make him suck its gona make your hormones increase the milk, have food increase your diet but now its not the same. Please help.