Search for the lepton number violation decay $\phi \to {\pi }^{+}{\pi }^{+}{e}^{-}{e}^{-}$ via $J\mathrm{/}\psi \to \phi \eta$

Using $(1.0087\pm 0.0044)\times {10}^{10}$ $J\mathrm{/}\psi$ events collected by the BESIII detector at the BEPCII collider, we search for the lepton number violation decay $\phi \to {\pi }^{+}{\pi }^{+}{e}^{-}{e}^{-}$ via $J\mathrm{/}\psi \to \phi \eta$. No signal is found and the upper limit on the branching fraction of $\phi \to {\pi }^{+}{\pi }^{+}{e}^{-}{e}^{-}$ is set to be $9.7\times {10}^{-6}$ at the 90% confidence level.