If this happens, time becomes of the essence: go to the airline desk immediately to check availability for the next flight and if the fare conditions of your ticket allow for rebooking (possibly with a surcharge).
Remember that for some airlines, if you've purchased round-trip airfare, the non-boarding of the passenger on the outward flight for reasons independent of the Carrier automatically results in the cancellation of the booking for the return journey, for which a reimbursement may be claimed according to the rules that apply to the purchased fare.
Don't forget that Amaka is always with you, even in these situations! Contact us through one of the contact channels available in the Customer Support section.