Spicejet Air Line - Not giving zero charge because flight booked earlier

We had a engagement in our family due to which we had booked flights across all our relatives and the bridegroom's family flight tickets to travel from Delhi to Chennai. Due to the rising number of corona cases in Delhi we decided to postpone the plan to June or July because it was not safe to travel as there were kids and old people on the same. We saw that Spicejet brought out an offer to change the booking made from date range **th April to **th May but there condition stated that the booking should have been done only after **th April, how would that be possible?
In such cases - we should never be given an option to book the flight earlier. Nobody is ready to help or even respond to us, very bad customer care service provided to the customers. We have been booking regular flights from them and everytime they end up re-scheduling. Now that we are requesting to give us an option to reschedule as the flight is booked for **th April, we are not even asking for a full refund giving a loss to them but they are least bothered abt their customers