Help with body velocity

I made it so when the combo of an attack is 5, the victim will get knocked back. However, ONLY the body velocity doesn’t work, everything else does. Please help.
Script:

local f = Instance.new("BodyVelocity",v.HumanoidRootPart)
f.Name = "PushForce"
f.MaxForce = Vector3.new(100000000,100000000,100000000)
f.Velocity = (-v.HumanoidRootPart.CFrame.LookVector) * 100
wait(0.25)
f:Destroy()
v.Humanoid:TakeDamage(dmg.Value*2)
Combo.Value -= Combo.Value

Usually its a network ownership and humanoid problem which prevents knockback from working. This method should guarantee both don’t interfere. If there is any other better method let me know since it seems to be a common problem.