we are using this code to subscribe from lightstreamer

var tableInfo = new SimpleTableInfo("sy1 sy2 sy3 sy4 sy5", "MERGE",
"adjustedYestClose AskPrice AskVol AvaragePrice"
, true) {DataAdapter = "PROXY_MarketBeat"};

_subKey = Tabee3Client.client.SubscribeTable(tableInfo, this, false);

the lightstreamer returns 2 snapshot the first snapshot have null values in all items in (IUpdateInfo collection) after i ends the lightstreamer send the second snapshot with the values.

what is the problem and how to solve it?