string expected, got object help?

So I keep getting the error, String expected, got object. Line 5: Bad argument #2 to '?'

NormalParts = {["Slab"] = true,["Wall"] = true,["Plate"] = true}
local event = script.BlockInsertation

event.OnServerEvent:connect(function(name)
local chil = game.Workspace[name]:GetChildren()
    for i, v in pairs (chil) do
        if NormalParts[v.Name] then
            local clone = workspace:FindFirstChild(name).Slab:Clone() or workspace:FindFirstChild(name).Wall:Clone() or workspace:FindFirstChild(name).Plate:Clone()
            clone.Parent = game.Workspace
        else
			script.Parent.MoneyDisplay.ErrorDisplay.Description.Text = "Undefined part value"
			script.Parent.MoneyDisplay.ErrorDisplay:TweenPosition(UDim2.new(0.8, 0,0.9, 0),"InOut","Linear",1,false)
			for i = 5, 1, -1 do
				wait(1)
				script.Parent.MoneyDisplay.ErrorDisplay.Timer.Text = i
			end
			script.Parent.MoneyDisplay.ErrorDisplay:TweenPosition(UDim2.new(1.3, 0,0.9, 0),"InOut","Linear",1,false)
			script.Parent.MoneyDisplay.ErrorDisplay.Timer.Text = "tim"
        end
    end
end)

I only looked at the first few lines of the script based on your error, so there may be another error later in the script.

The problem is that OnServerEvent takes two parameters. The first one MUST be the player, and the second is all the argument(s). You only have "name" which is what I'm assuming your argument. You just need to set player as a parameter.

Fixed Code:

NormalParts = {["Slab"] = true,["Wall"] = true,["Plate"] = true}
local event = script.BlockInsertation

event.OnServerEvent:connect(function(player, name) --The first parameter is the player, and the second one is all your arguments.
local chil = game.Workspace[name]:GetChildren()
    for i, v in pairs (chil) do
        for n, m in pairs(NormalParts) do
        if NormalParts[n] == v.Name then
            local clone = workspace:FindFirstChild(name).Slab:Clone() or workspace:FindFirstChild(name).Wall:Clone() or workspace:FindFirstChild(name).Plate:Clone()
            clone.Parent = game.Workspace
            break
        else
            script.Parent.MoneyDisplay.ErrorDisplay.Description.Text = "Undefined part value"
            script.Parent.MoneyDisplay.ErrorDisplay:TweenPosition(UDim2.new(0.8, 0,0.9, 0),"InOut","Linear",1,false)
            for i = 5, 1, -1 do
                wait(1)
                script.Parent.MoneyDisplay.ErrorDisplay.Timer.Text = i
            end
            script.Parent.MoneyDisplay.ErrorDisplay:TweenPosition(UDim2.new(1.3, 0,0.9, 0),"InOut","Linear",1,false)
            script.Parent.MoneyDisplay.ErrorDisplay.Timer.Text = "tim"
        end
        end
    end
end)

Here is the Wiki page on the event OnServerEvent.

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