Can someone tell me what I am doing wrong when changing a value in this datastore?

So I have these lines of code:

local function IncrementMoney(player)
	while true do
		wait(4)
		local PlayerStats = DataStoreService:GetDataStore("PlayerStatsTest"):GetAsync(player.UserId)
		print(PlayerStats)
		PlayerStats:IncrementAsync("Money", 10)		
	end
end

When it hits print(PlayerStats) it prints out this:

  {"DeckCount":1,"Wins":0,"Money":100,"Losses":0,"Reputation":0,"GamesPlayed":0,"LifePointsLost":0,"LifePointsDealt":0}

Yet when it goes to Increment "Money" it gives me this error: 15:48:07.950 - ServerScriptService.LoadPlayerData:181: attempt to call method 'IncrementAsync' (a nil value)