We use the Google Analytics Measurement Protocol to send offline transactions to Google Analytics. Sometimes we need to send two or more transaction with the same ID (and positive revenue). It works properly when we send transactions (with the same ID) in some days. However when we send two transactions (with the same ID) on interval of 1-2 minutes only one of them is considered in Analytics and another is ignored.
Is there any minimum interval between sending transaction with the same ID?
Code from comment:
$curl=curl_init(http://google-analytics.com/collect');
curl_setopt($curl,CURLOPT_RETURNTRANSFER,true);
curl_setopt($curl,CURLOPT_POSTFIELDS, 'v=1'.'&ni=1'.'&tid='.$track_id.'&cid='.$client_id . '&t=transaction'.'&ti='.$transaction_id.'&tr='.$revenue);
curl_exec($curl);
curl_close($curl);