List the 50 most recent top-ups for the current account

{  "success": true,  "purchases": [    {      "id": "string",      "pack_name": "string",      "credits": 0,      "amount": 0,      "currency": "string",      "kind": "credits",      "status": "pending",      "created_at": 0,      "paid_at": 0    }  ],  "property1": null,  "property2": null}