Problem with my request?

[lidder]

Can anyone see anything wrong with this request to place a bet?

{
"jsonrpc": "2.0",
"method": "SportsAPING/v1.0/placeOrders",
"params": {
"marketId": "1.114408479",
"instructions": {
"selectionId": "8506230",
"handicap": "0",
"side": "LAY",
"orderType": "LIMIT",
"limitOrder": {
"size": "2",
"price": "1.2",
"persistenceType": "LAPSE"
}
}
},
"id": 1
}

I am getting the following response...

{
u'jsonrpc': u'2.0',
u'id': 1,
u'error': {
u'message': u'DSC-0018',
u'code': -32602
}
}

Thanks

[lidder]

Missed out square brackets...

{
"jsonrpc": "2.0",
"method": "SportsAPING/v1.0/placeOrders",
"params": {
"marketId": "1.114408479",
"instructions": [{
"selectionId": "8506230",
"handicap": "0",
"side": "LAY",
"orderType": "LIMIT",
"limitOrder": {
"size": "2",
"price": "1.2",
"persistenceType": "LAPSE"
}
}]
},
"id": 1
}

[gus]

Don't think you should have quotes around the selectionId (which is a long) , and price, size and handicap (which are doubles).

For example my REST queries to placeOrders (which work) look like this:

https://api.betfair.com/exchange/betting/rest/v1.0/placeOrders/{"marketId":"1.114402505","instructions":[{"select
ionId":8484249,"side":"BACK","orderType":"LIMIT"," limitOrder":{"persistenceType":"PERSIST","price":3 .6,"size":4.0}}]}