Add a value overtime?

This script is not a loop, it only runs when the player joins. That is your issue, also, try to use ipairs, its more object based, its optional tho. I have tried using a while true do inside of a playeradded function and seems to not work by the way, I think repeat may be a good way to use it.

lvl1money = 2 -- the amount of money you get per second
game.Players.PlayerAdded:connect(function(player)
repeat
for i,v in pairs(game.Workspace.Mines:GetChildren()) do
    local money = player.leaderstats.Money.Value
     v.Name = math.random(1,100) --random names for all the goldmines
     wait(1)
     v.Collect.MoneyValue.Value = v.Collect.MoneyValue.Value + lvl1money -- adds money overtime to value in mine (collect)
    print(v.Collect.MoneyValue.Value)
end
end)