When this script that adds cash when smoke is active is running, it crashes my game?

It's because when you run "repeat until", it's adding cash infinite times per second, what do u need to fix it is making it wait:

game.ReplicatedStorage:WaitForChild("SpawnCar").OnServerEvent:Connect(function(player, NameOfCar)
    local car = game.ServerStorage.Cars:FindFirstChild(NameOfCar):Clone()
    local location = math.random(1,7)
    local spawnlocations = game.Workspace.World.SpawnLocations
    if location == 1 then
        car:SetPrimaryPartCFrame(spawnlocations.part)
    end
    if location == 2 then
        car:SetPrimaryPartCFrame(spawnlocations.part1)
    end
    if location == 3 then
        car:SetPrimaryPartCFrame(spawnlocations.part2)
    end
    if location == 4 then
        car:SetPrimaryPartCFrame(spawnlocations.part3)
    end
    if location == 5 then
        car:SetPrimaryPartCFrame(spawnlocations.part4)
    end
    if location == 6 then
        car:SetPrimaryPartCFrame(spawnlocations.part5)
    end
    if location == 7 then
        car:SetPrimaryPartCFrame(spawnlocations.part6)
    end
    car.Parent = workspace
    car:MakeJoints()
    car.Name = player.name.."'s "..NameOfCar
    car.Wheels.RR.ChildAdded:Connect(function(child)
        if child.Name == "Smoke" then
            repeat
                wait() -- you can add how many seconds you want it to wait until it rewards the money
                if child.Rate ~= 0 then
                    cash.Value = cash.Value + 10
                end
                until car == nil
        end
    end)