RankSystem is not a valid member of ServerScriptService "ServerScriptService"?

When I try to call a function from my module, I get an error. "RankSystem is not a valid member of ServerScriptService "ServerScriptService""

Script:

local module = require(script.Parent) -- This is the RankSystem module

while true do
    for _, player in pairs(game.Players:GetChildren()) do
        module.giveXPOrRankPlayer(player, 15)
    end 
    wait(420)
end

It basically says the script does not exist when it is litterly the parent of this script!