User Data Streams - Websocket: close 1008 (policy violation): Invalid request

Hi guys,

Currently, I want to listen outboundAccountPosition, balanceUpdate event.

Cuz i got error “websocket: close 1008 (policy violation): Invalid request” when trying to send request, my request is:
{
“method”: “REQUEST”,
“params”:
[
@account”, // request name 1
@balance” // request name 2, if existing
],
“id”: 12 // request ID.
}
Why is that? i’m sure that my listenKey is valid, Can you guys show me what wrong with my request?

BTW, I want do this in Spot and Future market.