Error - You can't use this filter as some of the conditions linked to it have been deleted.
You might come across an error message that states that you can’t use a filter since some of the conditions linked to it have been deleted.
This happens when a plan (or any other entity) associated with a particular filter is deleted from the site. For eg, let’s you have a plan named “premium plan”. Let’s say you have created a filter at the subscription level with the condition “plan includes premium plan” and other plans.
Now if the premium plan is deleted, you will face the above error, even though the other plans that are included in the filter condition are still active. Currently, there is no way to eliminate the deleted plan from the filter condition. To avoid this error, please make sure that, before deleting any plan, you remove that plan from all the filter conditions by editing the filters and then saving them.
Is it possible to filter set custom fields as filters via the APIs?