Help, the action plan does not update the status of the completed task but the task is in the finished state, what can I do

Is the intention to update associated Task status to completed?

If so.. you can use process builder automation..

It can be a process builder on action plan Object with a Field Update action.. on associated task record for status updates.

OR have a process builder/workflow rule on Task object itself to update status hen due date is past

https://help.salesforce.com/apex/HTViewSolution?urlname=Process-Builder-Update-Related-To-record-from-Task-or-Event&language=en_US