I couldn't find the relevant information via Google Search or existing FT threads, so here is a new thread!

Did a SDC on an already checked-in reservation and then upon attempting to check-in to the new reservation it fails on the last step (acknowledging prohibited items) and gives error code 301 and to check-in at the airport. Called AS Reservations who state there is nothing wrong on their and my reservation is set.

Does anyone know what a code 301 is?

update: at airport check-in the agent saw I was still booked and confirmed on both the original and new itineraries with confirmed seats on both.

check-in went just fine, not sure why AS Res couldn’t see this.