not have any money on handMeans that you do not currently have money with you, often implying that you cannot pay for something at that moment. It does not necessarily mean that you are generally poor or have no money at all.
JA: すみません、今お金の持ち合わせがないので、後で払ってもいいですか。
EN: Sorry, I don't have any money on me right now. Can I pay later?