VehicleSeat Returns Nil Throttle Value

Help and Feedback Scripting Support
#1

im making a car, and im having a problem:

code:

local seat = script.Parent.VehicleSeat

local steerAngle = 30
local speed = 60

seat:GetPropertyChangedSignal("Steer"):Connect(function()
	script.Parent.drivetrain.FL.sus_b.HingeConstraint.TargetAngle = steerAngle * -seat.Steer
	script.Parent.drivetrain.FR.sus_b.HingeConstraint.TargetAngle = steerAngle * -seat.Steer
end)

seat:GetPropertyChangedSignal("Throttle"):Connect(function(spd)
	print(spd)
	script.Parent.drivetrain.BL.steer1.HingeConstraint.AngularVelocity = speed * seat.Throttle
	script.Parent.drivetrain.BR.steer1.HingeConstraint.AngularVelocity = speed * -seat.Throttle
end)

everything is working fine, but in the throttle function, it doesnt work. i tried to check what the problem is by printing the amount, but i got nil in the output.

how do i fix this?