Boat not moving

Hello, I am trying to move a boat, yet it is not working, this is very simple but I cannot figure it out.
This is my script inside the vehicle seat

local boat = script.Parent.Parent
local seat = boat.VehicleSeat
local main = boat.Main

seat.Changed:Connect(function()
	main.AngularVelocity.AngularVelocity = Vector3.new(0, -1 * seat.Steer, 0)
	main.BodyForce.Force = seat.CFrame.LookVector * 10000 * seat.Throttle
end)

Listen to the VehicleSeat’s Throttle and Steer properties. Use :GetPropertyChangedSignal(“PropertyName”) to check if the player moved forward/backwards, left/right.

local boat = script.Parent.Parent
local seat = boat.VehicleSeat
local main = boat.Main

seat:GetPropertyChangedSignal("Throttle"):Connect(function()
	main.BodyForce.Force = seat.CFrame.LookVector * 10000 * seat.Throttle
end)

seat:GetPropertyChangedSignal("Steer"):Connect(function()
	main.AngularVelocity.AngularVelocity = Vector3.new(0, -1 * seat.Steer, 0)
end)

I get this error

 Workspace.Boat.VehicleSeat.Script:10: attempt to perform arithmetic (mul) on number and nil

Ah, I’ve made a minor nistake GetPropertyChangedSignal doesn’t return new values. My bad, I’ll edit my reply.