Diagnostocs information on device are null

Ignition
1

I try to see diagnostocs information on device (Siemens S7 driver)
tag in folder “[API1]_Meta:[Diagnostics]/Requests/@500ms” are null
other are ok ???

[attachment=0]error_diag.png[/attachment]

2

Do you have any related messages in the gateway console?
What does device diagnostics page look like? (In the Gateway Web Interface, go to Configure > OPC-UA / Devices, and click the Diagnostics link to the right if the entry for that PLC connection)
Do you have any tags from this device subscribed at 500 ms rate?
What version of Ignition is this?