Script to make player die upon joining, and only once?

Recently I switched from Data Persistence to Data Storage, and my level up script will not work until the player has reset after the first time joining, and I get errors saying "this is not a valid member of that" Until the player has reset. So I thought about instead of adding WaitForChilds in all of my scripts, I would just add a simple script that makes the player die and be forced to re-spawn when they join the game, to ensure that everything works right. Here is my attempt, which I could not get to work:

game:GetService('Players').PlayerAdded:connect(function(player)
    player.Character.Health = 0
    end

My attempt is so bad that it almost seems lazy to me, but then again, I've never been faced with this situation.

Any help is greatly appreciated, thank you.

Edit: Here is that Data Storage script and the Level up script

Data Storage:

local DSService = game:GetService('DataStoreService'):GetDataStore('Stats')
ID = 68 
SaveTime = 60
leaderboardname = "Levelss" --The name of the leader board

StatList = {Muny = 250 , Level = 1 , XP = 0 , FAP = 1 , RandomMove = 0 , RangedPunch = 0 }



function CreateValue(Name, Parent, Value) --If value is set to a number then new players will start with that amount.
    Value = Value or 0
    local savevalue =  Instance.new('IntValue', Parent)
    savevalue.Name = Name
    savevalue.Value = Value
    return savevalue
end

function GetValue(uniquekey)
    -- GetAsync
    local GetSaved = DSService:GetAsync(uniquekey)
    if GetSaved then
        return GetSaved
    end
end

game.Players.PlayerAdded:connect(function(plr)
    local uniquekey = ID..plr.userId
    local Levelss = Instance.new('IntValue', plr)
    Levelss.Name = leaderboardname
    for i,v in pairs(StatList) do
        local Stat = GetValue(i..uniquekey)
        if Stat then
            CreateValue(i, Levelss, Stat) --Old player load their value
        else
            CreateValue(i, Levelss, v) --New player load the default value
        end
    end
end)

game.Players.PlayerRemoving:connect(function(plr)
    local uniquekey = ID..plr.userId
    if plr:FindFirstChild(leaderboardname) then
        for i,v in pairs(StatList) do
            if plr[leaderboardname]:FindFirstChild(i) then
                DSService:SetAsync(i..uniquekey, plr[leaderboardname][i].Value)
            end
        end
    end
end)

while wait(SaveTime) do
    P = game:GetService("Players"):GetChildren()
    for o=1, #P do
        if P[o] then
            local uniquekey = ID..P[o].userId
            if P[o]:FindFirstChild(leaderboardname) then
                for i,v in pairs(StatList) do
                    if P[o][leaderboardname]:FindFirstChild(i) then
                        DSService:SetAsync(i..uniquekey, P[o][leaderboardname][i].Value)
                    end
                end
            end
        end
    end
end

Level up: (isnt 100% finished but it does still modify level so it's good enough for testing)

s = script.Parent
p = s.Parent
c = p.Character



p.Levelss.XP.Changed:connect(function()
if p.Levelss.XP.Value >= p.Levelss.Level.Value * 20 then
p.Levelss.XP.Value = 0
p.Levelss.Level.Value = p.Levelss.Level.Value + 1
p.Character.Humanoid.MaxHealth = p.Character.Humanoid.MaxHealth + 10
p.Character.Humanoid.Health = p.Character.Humanoid.Health + 10
p.Levelss.FAP.Value = p.Levelss.FAP.Value + 1
end
end)

Player.Character.Health = 0 This does like you set the character model's health to 0. Use Player.Character:FindFirstChild("Humanoid").Health = 0

There is a problem with roblox at the moment chatted is broken aswell.