Information needed about Rs.194 lifetime card

[dhoni]

There is one offer to get our number lifetime by paying Rs.194 and it will convert us to life time. Mine says valid upto 21-August-2021. But my doubt is whether I need to recharge a minimum of Rs.200 every six months to have it (in that case what is this validity meant for)? Getting some incoming calls will make it enough to keep my number active?