In detail
The portal FAQ gives the same answer to all three questions: once a booking is successfully confirmed,
- it cannot be rescheduled; to submit on another day you must make a new booking
- it cannot be cancelled
- it cannot be transferred; a slot booked for one applicant cannot be used by another
So before you pick a date, be sure you can be at the centre that day. The FAQ says nothing about a refund on cancellation, and neither do we.
Two more things the FAQ says:
- if payment fails the booking is not confirmed; you may retry, or restart the booking, subject to slot availability
- everyone under the same Transaction ID is treated as one group and must report together at IVAC. Booking through an agent risks being grouped with strangers, so book yourself, and check who is on the transaction afterwards