Hi there, @fok_ste… if I understand your post and your screenshot correctly, you put a condition on the input element that says when the input’s value is not unique, the input must not be empty. With that condition in place, the system will create a duplicate entry because it is only checking to make sure the input is not empty as opposed to stopping the creation of a new thing because the input’s value is the same as one that already exists.
You should remove the condition from the input element and put a similar condition (although, I would likely change it form
is 1 to
> 0 so the system can stop searching as soon as the count is greater than 0) on the submit button that prohibits the button from being clicked when the condition is true. You could also consider having the first step in the submit button’s workflow be a step that terminates the workflow only when the input’s value is not unique.
Hope this helps.