for some reason after freezing my character and unfreeze it, it stays frozen?

here's the part of the script that isn't working. When I play this animation it stops the player to play it and then you wait some time for it to unfreeze, but when I do it the player is just stuck there????

local StartUpAnimation = hum:LoadAnimation(script.StartUp)
		local SUW = script.StartUpWoosh
		local hitBox =  game.ServerStorage.HitBox:Clone()
		hitBox.Parent = workspace
		hitBox.CFrame = humrp.CFrame + humrp.CFrame.LookVector*3
		game.Debris:AddItem(hitBox,1)
		
		local weld = Instance.new("WeldConstraint",hitBox)
		weld.Part0 = humrp
		weld.Part1 = hitBox
		
		SUW:Play()
		StartUpAnimation:Play()

		local FreezeSU =  Instance.new("BodyVelocity")
		FreezeSU.Parent = humrp
		FreezeSU.Velocity = humrp.CFrame.LookVector*.001
		FreezeSU.MaxForce = Vector3.new(100000,100000,100000)

		wait(.4)

		game.Debris:AddItem(FreezeSU,0)