DataStore not working? No error.. Kind of copied a video but changed it up.

The problem is that you are calling SetAsync in the else statement in the playeradded event. You need to realise that that method yields the script until the data is found and considering that your providing the else statement with the fact it has no data to save; it will yield it forever. Here is the fix:

--MAKE SURE IT IS A SERVERSCRIPT IN SERVERSCRIPTSERVICE
local DataStoreService = game:GetService("DataStoreService"):GetDataStore("Hello")
game.Players.PlayerAdded:Connect(function(plr)

    local uniquekey = "id-"..plr.userId
    local leaderstats = Instance.new("IntValue",plr)
    local savevalue = Instance.new("IntValue")
    local savevalue2 = Instance.new("IntValue")
    local savevalue3 = Instance.new("IntValue")
    leaderstats.Name = "leaderstats"
    savevalue.Parent = leaderstats
    savevalue.Name = "Money"
    savevalue2.Parent = leaderstats
    savevalue2.Name = "Subscribers"
    savevalue3.Parent = leaderstats
    savevalue3.Name = "Followers"

    local GetSaved = DataStoreService:GetAsync(uniquekey) or {} --Checks if there is data to load
    if GetSaved then
        savevalue.Value = GetSaved[1] or 0 --If there is no data then just give it a default of 0.
        savevalue2.Value = GetSaved[2] or 0 --If there is no data then just give it a default of 0. 
        savevalue3.Value = GetSaved[3] or 0 --If there is no data then just give it a default of 0.
	--Since we have already certified any errors appearing if the data is nil, there is no need for the else statement.
	end
end)

game.Players.PlayerRemoving:connect(function(plr)
    local uniquekey = "id-"..plr.userId
    local Savetable = {plr.leaderstats.Cash.Value, plr.leaderstats.Subscribers.Value, 				 
    plr.leaderstats.Followers.Value}
    DataStoreService:SetAsync(uniquekey, Savetable)
end)