FlyerTalk Evangelist
Join Date: Feb 2009
Location: From ORK, live LCY
Programs: BA Silver, EI Silver, HH Gold, BW Gold, ABP, Seigneur des Horaires des Mucci
Posts: 14,209
Could be any of a number of things, including that the system doesn't like your COVID paperwork, you've uploaded it to the wrong system, the system has decided your passport needs physical inspection, you've been SSSSelected, or your ticket's invalid (least likely). Almost certainly, the airport will sort it out.