Absolute convergence implies convergence .

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Absolute convergence implies that

$ \mid \mid s_m\mid −\mid s_n \mid \mid \space = \space \mid \mid x_{m}\mid +\mid x_{m−1}\mid +…\mid x_{n+1} \mid \mid \space \leq \space ϵ $

But $\mid s_m −s_n\mid \space = \space\mid x_{m} + x_{m-1} +… x_{n+1}\mid $

$ \because \space \mid x_{m} + x_{m−1} +… x_{n+1}\mid $ $\leq$ $ \mid \mid x_{m}\mid +\mid x_{m−1}\mid +…\mid x_{n+1} \mid \mid $ = $ \mid \mid s_m\mid −\mid s_n \mid \mid $

So $\space \mid s_m −s_n\mid \space \leq$ $ \mid \mid s_m\mid −\mid s_n \mid \mid $

Which is a contradiction. What is wrong in this ?