Cant get LPV to work for the life of me

I have tried getting lpv to work for 4 days now and nothing has worked so far i have tried uninstalling ue4 3 times that hasn’t worked i all ways make sure to add r.LightPropagationVolume = 1 to the config i restart and nothing shows up. i get the options for it and when i click show lpv the text comes up saying its working but. there is no visible sign it is working i have cranked all the setting to max and nothing shows up i followed alot of steps. even the steps epicgames outlines for set up. hope you guys can help.