As the name suggests, you can cancel your flight ticket within 24 hours of booking. Here are the rules of the policy.

If you cancel your ticket within 24 hours of your purchase, you will not be charged for canceling your Aeromexico trip.
If you have booked seven days or more prior to the departure date of the flight, you can refund the refund in full.
If you have made a reservation within seven days after the trip, the appropriate amount will be deducted from your account.
Ticket purchases are made 24 hours a day, and cancellation fees are charged.
If you have booked a return ticket, you are entitled to a full refund.
If you have booked a non-refundable ticket, you will have to pay for the cancellation, depending on the Aeromexico refund policy.
Aeromexico cancellation policy would apply to refundable and non-refundable fares.
Aeromexico will refund the person who purchased the ticket or the passenger who requested the cancellation directly.
Aeromexico would only be responsible for the part of the ticket that was not used.
Passengers can request that Aeromexico cancel a flight up to two hours before the scheduled departure time.