Self-interaction among the neutrinos in the early Universe has been proposed as a solution to the Hubble tension, a discrepancy between the measured values of the Hubble constant from CMB and low-redshift data. However, flavor-universal neutrino self-interaction is highly constrained by BBN and several laboratory experiments such as, tau and K-meson decay, double-neutrino beta decay etc. In this talk, I will discuss about the cosmology if only one or two neutrino states are self-interacting. Such flavor-specific interactions are less constrained by the laboratory experiments. Finally, I will talk about the feasibility of addressing the Hubble tension in the framework of such flavor-specific neutrino self-interaction.