  We consider the gauged $B-L$ model which is extended with a secluded dark
sector, comprising of two dark sector particles. In this framework the lightest
$\mathcal{Z}_2$-odd particle is the dark matter candidate, having a feeble
interaction with all other SM and BSM states. The next-to-lightest
$\mathcal{Z}_2$-odd particle in the dark sector is a super-wimp, with large
interaction strength with the SM and BSM states. We analyse all the relevant
production processes that contribute to the dark matter relic abundance, and
broadly classify them in two different scenarios, a) dark matter is primarily
produced via the non-thermal production process, b) dark matter is produced
mostly from the late decay of the next-to-lightest $\mathcal{Z}_2$-odd
particle. We discuss the dependency of the relic abundance of the dark matter
on various model parameters. Furthermore, we also analyse the discovery
prospect of the BSM Higgs via invisible Higgs decay searches.
