There are two OPC tags
WasteCount，WasteCode
When WasteCount + 1 is used, the Transaction Group is used to record data
The rate is 300
ID WasteCount WasteCode t_stamp
1 1 1001
But you lose a fraction of your data a day 5%,
Other software has been used to record using the same PLC connection without loss
How should I diagnose the cause of the loss😩
Do you mean 300ms? That is quite fast if there is anything else being monitored there. Consider using OPC items instead of Ignition tags, and setting the transaction group to OPC "Read" mode instead of "Subscribed".
Those are tag references. You need OPC items.
I've been running this configuration for a while, but I still find some data missing. It's a little bit better than before. This is my configuration, I am not sure if the OPC items you said were created like this 
Are you sure that the PLC is setting the Code before the Count? (The trigger must be the last thing changed in the PLC.)
