This is usually due to the user not having the correct user profile permissions and can be rectified by following the steps below.
Check that you are permitted to view/amend specific users tasks.
Enter the User Profiles program.
Select the User, and click UPDATE.
Select the TASK DIARY tab.
Navigate to the Tasks of Other Users/Groups area.
Click the Load Privilege Settings button.
Select the Allow this user to view tasks of these users/groups radio button.
Ensure the appropriate users are ticked.
Select the Allow this user to amend or delete of these users/groups radio button.
Ensure the appropriate users are ticked.
Click SAVE and EXIT.
Check you have other permissions to amend/action tasks.
Enter the User Profiles program.
Select the User, and click UPDATE.
Select the AUTHORISATIONS tab.
Navigate to the Tasks Screen area.
Ensure the appropriate authorisations are ticked.
Navigate to the Task Deletion area.
Ensure the appropriate authorisations are ticked.
Click SAVE and EXIT.
If you or your System Administrator does not have access to User Profiles, please raise a new case online and reference the title of this article.