With regular task that a re occurring based on time or counts the oldest task must be completed first. It can be that multiple tasks are open ie not completed, and if you do not select the oldest you will not see the "Confirm service"
For Example:-
Here I have tasks 2 over due and 2 in the future
If I select the tasks from the 28th July which isn't the first I will see the task - but without the additional data - AS the prir task isn't completed.
The prior task on the 2nd July show all the data :-
Here I can confirm the service.
In this case it was easy to spot once I filtered the tasks by dates and device / locations so I see all the re occurrences and can identify the oldest.