Why is my DataStore so inconsistent?

Hey, so my datastore kind of sucks because it isn't consistent and it somehow will save my stats as someone elses sometimes, its really odd and i cant figure out why?

If you guys see anything that would make this not work please let me know, thank you!

--Variables
local leveldata = game:GetService("DataStoreService"):GetDataStore("level")
local EXPdata = game:GetService("DataStoreService"):GetDataStore("EXP")
local xpLeveldata = game:GetService("DataStoreService"):GetDataStore("xpLevel")
local Golddata = game:GetService("DataStoreService"):GetDataStore("Gold")
local toolsdata = game:GetService("DataStoreService"):GetDataStore("Tools")
local HttpService = game:GetService("HttpService")

level_gold = {"Gold", "Level"}
EXP_EXPNeeded = {"Exp" , "ExpNeeded"}

--Data Storage Save
function savedata(dataname, playerid, value)
    game:GetService("DataStoreService"):GetDataStore(dataname):setAsync(playerid, value)
end

--Leaderboard Variables
game.Players.PlayerAdded:Connect(function(player)
    playerKey = "user."..player.UserId  -- user key
    print(playerKey)
    local leaderstats = Instance.new("Folder")
    leaderstats.Name = "leaderstats"
    leaderstats.Parent = player

    --Gold
    local gold = Instance.new("IntValue")
    gold.Name = "Gold"
    gold.Value = Golddata:GetAsync(playerKey) or 0
    gold.Parent = leaderstats


    --Level
    local level = Instance.new("IntValue")
    level.Value = leveldata:GetAsync(playerKey) or 1
    level.Name = "Level"
    level.Parent = leaderstats



    --XP
    local EXP = Instance.new("IntValue")
    EXP.Value = EXPdata:GetAsync(playerKey) or 0
    EXP.Parent = player
    EXP.Name = "Exp"

    --XP Needed
    local xpLevel = Instance.new("IntValue")
    xpLevel.Value = xpLeveldata:GetAsync(playerKey) or 84
    xpLevel.Name = 'ExpNeeded'
    xpLevel.Parent = player

    --tools
    local tools = toolsdata:GetAsync(playerKey)
    if tools then
        for i,v in pairs(tools) do
            local tool = game.ReplicatedStorage.Tools:FindFirstChild(v)
            if tool then 
                tool:Clone().Parent = player.Backpack
                tool:Clone().Parent = player.StarterGear                    
            end
        end
    end

--Save data when player leaves
game.Players.PlayerRemoving:Connect(function(player) -- save player stats
    local toolsToSave = {}      
    for i,v in pairs(player.StarterGear:GetChildren()) do
        if v then
            table.insert(toolsToSave,v.Name)
        end
    end
    game:GetService("DataStoreService"):GetDataStore('Tools'):SetAsync(playerKey, toolsToSave)
    savedata('level',playerKey,player.leaderstats.Level.Value)
    savedata('EXP',playerKey,player.Exp.Value)
    savedata('xpLevel',playerKey,player.ExpNeeded.Value)
    savedata('Gold',playerKey,player.leaderstats.Gold.Value)
    print('data saved')
end)

I know i use alot of separate DataStores instead of putting them into a table, (mainly because i dont know how to put them into a table.) but do you think that would be a enough reason for this not to work??