Animation Not Playing Fully?

So I created a custom sitting animation using the animation editor, basically when you sit on a couch im wanting it to lean you back and place your arms kinda to your sides and w/e.

So I made the animation for that but when you sit on the seat, the animation plays for like .2 seconds then it just goes to the normal sitting animation.

Code attached.

seat = script.Parent
function added(child)
    if (child.className=="Weld") then
        local human = child.part1.Parent:FindFirstChild("Humanoid")
        if human ~= nil then
            anim = human:LoadAnimation(seat.sitanim)
            anim:Play()
        end
     end
end

function removed(child2)
    if anim ~= nil then
        anim:Stop()
        anim:Remove()
    end
end

seat.ChildAdded:connect(added)
seat.ChildRemoved:connect(removed)