So through an event I use my SCP867Service:Test onto my Effect’s module

--Service script
function SCP867Service:Test(player)
    Effect.Apply(self.PrintSomething, player, 10, 1, "Test")
    wait(5)
    Effect.Remove(self.PrintSomething, player, "Test")
end

--Module script
function effect.Apply(func, player, duration, tickSpeed, tag)
    
    --Check if the player already has the effect, bad code we don't check nil cases
    local owningPlayer = game.Players:GetPlayerFromCharacter(player.Parent)
    if effectsStorage[owningPlayer] and not Macros.findValue(effectsStorage[owningPlayer], func) then
        --Adding to all tables
        local functionCoroutine = coroutine.create(function()func(player, duration, tickSpeed)end)

In debugging the values look correct, with the player being the humanoid I passed, duration being 10 and tickSpeed being 1. Which then executes a function in the original service script:

function SCP867Service:PrintSomething(player, duration, tickSpeed)
    for i = 1, duration, 1 do
        print("Testing count: ", i)
        task.wait(tickSpeed)
    end
end

However here player = 10, duration =1 and tickSpeed = nil
What causes this?

I did all debugging I could and found that somewhere between the module script and the function being executed in my coroutine an additional value was required. I added a patch work solution of passing an additional nil before my player to make my code work, but doesn’t seem like the proper solution.

local functionCoroutine = coroutine.create(function() func(nil, player, duration, tickSpeed)end)