We received debit memo for tickets without endorsement, this debit subjected to dispute it because my reason is that the endorsement is not the responsibility of the agent who issued the ticket, nor is the GDS, because the endorsement appears automatically as long as the airline has filed this restriction through ATPCO, otherwise if they forgot the debit is not valid.
But the airlines don’t accept my answer.

Could help to clarify whether I’m right or my answer is wrong.

Thanks in advance for your help.

Sincerely,

Elizabeth Castillo
ARC Audit, Travel Dept.