As for the cancellation of Avianca airlines, that is not the inconvenience lets see the Avianca cancellation policy
Avianca Airlines Cancellation Policy
Avianca does offer a 24-hour cancellation policy for passengers traveling to and from the United States under a 24-hour policy; if you cancel your flight within 24 hours of booking and 7 days before departure, the airline allows you to cancel your flight free of charge with a full refund.
However, if you fail to complete the cancellation procedure within the stipulated period, you will be required to pay the cancellation fee.
Cancellation fees depend on the fare type/rules that apply to you at the time of booking.
The 24-hour policy applies to all tickets, whether refundable or non-refundable.
According to the airline's cancellation policy, if you have a refundable ticket and cancel your flight after 24 hours, you will get the airline's refund less the cancellation fee. If you hold a non-refundable ticket and cancel after 24 hours, you will not be eligible for a refund, but will receive points for future travel.