can be alleviated if the sterile neutrino is produced in a scenario where the reheating temperature ($T_R$) is low, $T_{R} < 7$ MeV. The authors of [@Saviano:2013ktj] have shown how to reduce $N_{\nu}$ by studying the active-sterile flavor conversion. In [@Ho:2012br], they have used MeV dark matter to reduce $N_{\nu}$ with the help of $p$-wave annihilations. Ref.[@Giovannini:2002qw] discuss about the fact that without violating cosmology we can increase the relativistic [*d.o.f*]{} by reducing the neutron to proton ratio ($n/p$). A number of these possible resolutions can be applied for our model. For example, we can consider the existence of secret interactions with some hidden sector particles which would help lower the neutrino mixing between the left-handed and right-handed neutrinos. The effect of these interactions though would have ceased to exist at a much earlier time in the universe and today we will not be able to observe them anymore. Hence our current study would not be sensitive to them. Again, the other two right handed neutrinos are in MeV mass range and have a warm spectrum [*i.e.*]{} they are neither relativistic (which makes the problem with the cosmological structure formation [@Abazajian:2004zh]) nor non-relativistic. Extensive studies in the context of structure 