Error with DataStore. Help?

So, I'm trying to make a leaderboard where it displays the level of a player using the script below:

local DataStore = game:GetService("DataStoreService"):GetDataStore("Level")

game.Players.PlayerAdded:connect(function(player)
    local leaderstats = Instance.new("IntValue", player)
    leaderstats.Name = "leaderstats"

    local levelstats = Instance.new("IntValue", leaderstats)
    levelstats.Name = "Level"

    local key = "user_" .. player.userId
    player.leaderstats.Level.Value = DataStore:getAsnyc(key)
    if DataStore:getAsnyc(key) == 0 then
        DataStore:setAsync(key, 1)
        local connection = DataStore:OnUpdate(key, function(value)
            player.leaderstats.levelstats.Value = DataStore:getAsnyc(key)
        end)
    end
end)

Whenever I run it, I get this error: 16:32:21.444 - getAsnyc is not a valid member of GlobalDataStore 16:32:21.445 - Script 'Workspace.Leaderstats', Line 13

What's wrong with the script? I have found no reason why getAsnyc would not work for DataStore. Please help me!