Zabbix SNMP how to delay trigger

[tty]

Good afternoon.
At the moment, we receive notifications about running out of toner in the cartridge from Zabbix. Zabbix collects toner volume information via SNMP. Everything works, but there is a problem that sometimes SNMP on the printer gives a false value (0) for a while and the trigger fires accordingly on Zabbix.
The current implementation is

100*last(/Template SNMP Kyocera/.1.3.6.1.2.1.43.11.1.1.9.1.3)/last(/Template SNMP Kyocera/.1.3.6.1.2.1.43.11.1.1.8.1.3)<=10

I want the trigger to only fire if the toner is <=10 for 30 minutes. So I can get rid of false positives.

Tried doing this but it doesn't work

max(100*last(/Template SNMP Kyocera/.1.3.6.1.2.1.43.11.1.1.9.1.3)/last(/Template SNMP Kyocera/.1.3.6.1.2.1.43.11.1.1.8.1.3), 30m)<=10

Thanks in advance for help!

[tty]

I also want to add.
I tried adding an item that calculates the amount of remaining toner

and changing the trigger

the trigger started to work, but the delay does not work. those. trigger fires instantly

[Mitchpeter]

There is an OID for hrPrinterDetectedErrorState at 1.3.6.1.2.1.25.3.5.1.2.
Bit 0 (128) = low paper etc. If this shows no toner the printer has really run out (not just very low).