When traveling internationally, if your checked baggage is delayed, you have rights under the Montreal Convention. This law outlines the airline's liability for delayed, damaged, or lost luggage.

In the case of delayed baggage, you can claim for reasonable and necessary expenses incurred while waiting for your luggage. This includes costs for toiletries, clothing, and other essentials that you needed during the delay.

To support your claim, it is crucial to keep all receipts and document your expenses. You should also report the missing bag at the airport, which you have already done.

Your next step is to submit a formal written claim to the airline within 21 days of receiving your luggage. Include all relevant details such as flight information, baggage tag, receipts, and a Property Irregularity Report (PIR). This report is essential for your claim, as many airlines require it.

If the airline does not respond satisfactorily, you can seek assistance from the European Consumer Centre Ireland (ECCI), which offers free services to help with cross-border complaints.