Not able to Submit or Approve the task

Summary:

Task:

Update task progress in the "Close Schedule" - Task Manager - End User 

Approve task progress in the "Close Schedule" - Task Manager – Approver 

Result: not able to approve or update the "close schedule"

What could be the cause? We have the Task Manager All Roles. It may be due to the schedule. Is there a way to copy it from Prod to Test?

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