  In this article, we investigate the convergence rate of the discrete-time
Clark--Ocone formula provided by Akahori--Amaba--Okuma [1]. In that paper, they
mainly focus on the $L_{2}$-convergence rate of the first-order error estimate
related to the tracking error of the delta hedge in mathematical finance. Here,
as two extensions, we estimate "the higher order error" for Wiener functionals
with an integrability index $2$ and "an arbitrary differentiability index."
