Is it possible to add values to an existing DataStore?

Hey all, I have an existing datastore containing player data that I want to add a new value too.

Here is the code I used. When I first coded this into my game, I created it with Points, Survivals, Level, and XP as the only values. Now that I have added the Colour value, it won't save/load to previously existing player data, presumably because I'm trying to update a value that does not exist in their datastore. (leaderstats is what appears on the leaderboard, and hiddenstats are stats that aren't public to others)

local Data = game:GetService('DataStoreService'):GetDataStore('Data0')

local prefix = 'user_'

game.Players.PlayerAdded:connect(function(player)
	local leaderstats = player:WaitForChild("leaderstats")
	local hiddenstats = player:WaitForChild("hiddenstats")
	local points = leaderstats:WaitForChild("Points")
	local survivals = hiddenstats:WaitForChild("Survivals")
	local level = leaderstats:WaitForChild("Level")
	local xp = hiddenstats:WaitForChild("XP")
	local colour = hiddenstats:WaitForChild("Colour")

    local plrData = Data:GetAsync(prefix  .. tostring(player.UserId))

    if plrData then
          points.Value = plrData[1] or 0
          survivals.Value = plrData[2] or 0
          level.Value = plrData[3] or 1
          xp.Value = plrData[4] or 0
          colour.Value = plrData[5] or 7
    else

    Data:SetAsync(prefix  .. tostring(player.UserId), {
        points.Value,
        survivals.Value,
        level.Value,
        xp.Value,
        colour.Value        
     })
   end

end)

game.Players.PlayerRemoving:connect(function(player)
    Data:SetAsync(prefix  .. tostring(player.UserId), {
        player.leaderstats.Points.Value,
        player.hiddenstats.Survivals.Value,
        player.leaderstats.Level.Value,
        player.hiddenstats.XP.Value,
        player.hiddenstats.Colour.Value
    })
end)

I think I understand the problem, but I'm not entirely sure how I could work this into my code. Any help or suggestions would be greatly appreciated!

I don't think there is a way to edit an existing DataStore unless you use the DataStore Editor plugin as of here.