Traženi pojam: Why was I charged for storage while collecting my item at the post office?

Why was I charged for storage while collecting my item at the post office?
Storage is charged for all items weighing over 500 grams which are not collected within one day after the receipt of the item arrival notification. Storage charge for the items for which the customs post office has sent a summons for delivery of documents for the customs inspection starts 10 days after the date of the summons’ sending.