Existence of extension of isometries on subspaces of $\ell_{p}(\mathbb N)$.

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Consider $\ell_{p}(\mathbb N)$ with $p\in\{1,\infty\}$. Let $Y\subseteq\ell_{p}(\mathbb N)$ be a closed linear subspace and $\varphi\colon Y\rightarrow Y$ a (not necesserily surjective) isometry.

Can this isometry be extended to an isometry, i.e., $\overline{\varphi}:\ell_{p}(\mathbb N)\rightarrow\ell_{p}(\mathbb N)$ with $\overline{\varphi}\mid Y=\varphi$?