Make start times unavailable by blocking them in the Availability View (Recommended)
As an administrator, you can do this from Availability in the left-hand menu. Read more about it here.
Close a product using product capacity
By setting the product's capacity to 0, you make the product unavailable. You can create a new capacity schedule within the product settings > availability > Capacity & Schedule.
Create a new capacity schedule
Set 'Max Capacity' to 0.
Note! If you have manually specified start times, you also need to set the capacity to 0 for all start times to completely close the product. Don't forget to prioritize your schedule if have multiple ones.
Define the period for which this capacity should apply.
Save! 🔒
You can read more about how to change capacity here.
Close a product via opening hours
For a product to be closed in this way, it needs to be linked to the opening hours. The product should not have the start time type set to Manually entered start times regardless of opening hours.
Go to Settings > Opening hours
Add new opening hours
Specify the period during which the product should be closed and check "Close"
Select which products the period should apply to.
Save 🔒 Don't forget to place your new period at the top of the priority order!

