Acked Alarm Eventtime not getting update when alarm cleared

I’m using Ignition 8.0.15. I realised that all my alarms’ eventtime won’t update after someone ack’ed them.

As shown in the photo above, the alarm is ack’ed on 9.26am and the eventtime updated to 9.26am, but it stay there even after the alarm is cleared on 4.02pm.

Does anyone has idea about this?