Assuming you are seeing this strange error when trying to save a new discount function.
And you’re confused, well, here’s the answer!
Shopify limits only 25 automatic functions to be live at a given time on a specific store which means, you can’t enable the 26th automatic function combined from all the apps including public and custom apps!
An alternate option is to use Discount code for the function and that will work without any issues as the limitation only applies to an automatic discount code.
