An Post & AddressPal Small Claims Query

Brief summary of what happened: Ordered an item from eBay and had it delivered to AddressPal. Item was delivered successfully and forwarded to An Post for delivery once the outstanding customs charges were paid. An Post delivered the item to a Parcel Locker in my home town before custom charges were paid. The same day the parcel locker was removed from its location with my parcel still inside.

Customs charges were paid 10 days later and I expected delivery. After a week I queried the status of my delivery. An Post told me that the item had been successfully delivered and that they could do nothing about it. They also told me to contact AddressPal to raise a claim.

I contacted AddressPal who informed me that the item cannot be located either here or back in the UK. They also say that the maximum claim I can pursue is 200Euro for the item.

My question is this, can I take a small claims court action against An Post for the full cost of the lost item (which was twice what AddressPal say they will payout)? They have admitted in an email that the item was delivered to a parcel locker before customs charges were paid and that the parcel locker was removed with the contents still inside.

Any help would be appreciated.