If you can't allocate or unallocate on the planning screen because you don't see these options, make sure you have the Auto-Refresh bar disabled in the top right.
You can move this to show green by clicking on the ball icon and dragging to the left to disable this.
If this isn't the case, please check the users' modules and functions to see which are disabled and which are available by following these steps.
Modules & Functions
By default, newly created users have access to all modules and functions. To restrict these permissions.
Click Settings, then click Other.
Click Profiles & Users, then click Users.
Select the relevant user.
Above Security Access, click Modules & Functions.
Select the planning module for the user.
Ensure the following are not ticketed to disable.
Updateable timeline.
Update End time.
Updateable.
Timeline.
If you are still unable to do this, please raise a new case online and reference the title of this article.
Name of User affected.
Steps taken to allocate or unallocate visits.