Some people can jump infinitely high with a gravity coil. Is this some sort of weight issue?

The title should say it all.

Here's my code:

script.Parent.Equipped:connect(function()
    character = script.Parent.Parent
    if character:FindFirstChild('HumanoidRootPart') then
        for i,v in pairs(character.HumanoidRootPart:GetChildren()) do
            if v.Name == "JUMPHIGH" then
                v:Remove()
            end
        end
        local BodyForce = Instance.new("BodyForce", character.HumanoidRootPart) 
        BodyForce.Name = "JUMPHIGH" 
        BodyForce.force = Vector3.new(0,0,0)
        for a, prt in pairs(character:children()) do 
            if prt:IsA("BasePart") then 
                BodyForce.force = BodyForce.force + Vector3.new(0,prt:GetMass()*90,0) 
            elseif prt:IsA("Accoutrement") then 
                BodyForce.force = BodyForce.force + Vector3.new(0,prt.Handle:GetMass()*90,0) 
            end 
        end
    end
end)

script.Parent.Unequipped:connect(function()
    if character:FindFirstChild('HumanoidRootPart') then
        for i,v in pairs(character.HumanoidRootPart:GetChildren()) do
            if v.Name == "JUMPHIGH" then
                v:Remove()
            end
        end
    end
end)

Does anyone have any idea what could be going wrong? In a few rare cases, I've seen players getting stuck in the ceiling because they're jumping infinitely high. Nobody is exploiting or anything, there's something going wrong with this script :).

I haven't identified what the players this affects have in common, but people have been reporting it (and I have seen it happen) in my game.

Thanks for any help :)