As your An Post delivery is from outside the EU, Irish Revenue have applied a Customs Charge. This Customs Charge must be paid to An Post within 16 working days in order for your item to be released for delivery.
Tracking ID format: AB 1234567 IE
Your Customs reference number is located on your Customs Charge Notification Card.
Can’t find your Customs reference number?
About Customs Charges
Your Customs reference number or Master Reference Number (MRN) is a unique customs
declaration number which can be located on your Customs Charge Notification Card as shown in the example below.
If you have received a customs payment request from An Post through SMS or email you can use the link provided to you in the SMS or email.