Timer event is not working properly in version 7.6

For some of the flows in the BPMN I can see the timer is getting executed and I can see a delay i.e. 5 secs and for some flows in BPMN, I can see even though timer was executed but it didn’t get delayed. So its kind of 50-50 scenario, so not able to understand whats wrong. Its kind of a harcoded value i.e. PT5S which I have set for timer.

Camunda version which I am using is 7.6.