CallbackPayload
{
"event": "order.created",
"timestamp": 1722412800,
"nonce_str": "a1b2c3d4e5f6g7h8i9j0k1l2m3n4o5p6",
"data": {},
"sign": "A3F8B2C1D4E5F60718293A4B5C6D7E8F"
}{
"event": "order.created",
"timestamp": 1722412800,
"nonce_str": "a1b2c3d4e5f6g7h8i9j0k1l2m3n4o5p6",
"data": {},
"sign": "A3F8B2C1D4E5F60718293A4B5C6D7E8F"
}