From your ZenMaid dashboard, go to Scheduling > Calendar View (or any other view you prefer).

Click on a recurring appointment.

On the appointment details window to your right, click the Actions button and select Manage Recurring Service.

On the Manage Recurring Service page, find the section Default Appointment Information.

Under Notes, click the Change Work Items, Custom Fields & Notes.. button.

On the pop-up window, check/uncheck the work items.

Under step 2, select which date you want the changes in work items to take effect.

Finally, click on the Change service details for the cleanings selected button.