How to install ELS properly

I installed the luxart systems (ELS) into my client side fivem and GTA 5 the lights work but no siren it’s all ways worked before but after not having it for a while and reinstalling it I don’t know if I have done it right . If anyone can send a link or explain it would be great thanks

search for luxart vehicle control on fivem forums (here lol) it controls sirens serverside.