A user with limited rights has rights to edit the template.
The template is nested to two other templates, to one of which the user does not have permission to edit and does not have access to the hostgroup of the template and hosts
The user adds an item to the template. The item appears only on those hosts to which the user has rights, no errors occur. Next, the user tries to add a trigger with this item to the template. An error occurs that a certain host does not have such item.

The trigger could not be created in the templates section because the item was not replicated to the host. In turn, the item on the host does not bind due to the lack of rights (on the host) of the user

The most probably items should be created on each host the template is linked (even via nested templates)