  In this paper, we extend the Standard Model (SM) scalar sector with scalar
leptoquarks (LQ) as a portal to the dark sector to resolve some observational
anomalies simultaneously. We introduce LQ coupling to scalar dark matter (DM)
to suggest an exotic decay channel for the neutron into scalar DM and an SM
anti-neutrino. If the branching ratio of this new neutron decay channel is
$1\%$, a long-standing discrepancy in the measured neutron lifetime between two
different experimental methods, bottle and beam experiments, can be solved. The
mass of the scalar DM produced from neutron decay should be in a narrow range
and as a result, its production in the early universe is challenging. We
discuss that the freeze-in mechanism can produce this scalar DM in the early
universe with the correct relic abundance. Then we show that the model can
explain other SM anomalies like the muon $(g-2)$, and $R_{D^{(*)}}$ anomaly
simultaneously.
