Thanks for your response!
The solution you offered Jochem, will give a new problem.
Every month an automation flow will run, and in one batch will create 10 invoices (with number 1-10).
If the supplier checks all invoices, and delete for example number 6 this number will be stored.
But this number will only be filled, when the automation flow will run again. So then invoice number 6 is later then number 7-10.
What actually needs to happen, is when a supplier deletes number 6. All the invoices that haven’t been captured yet need to be updated so that number 6 gets filled again. Then the invoices will only go until number 9 or something like that. The only issue is that when a user deletes number 6, and numbers 7,8,9 are captured already a new issue arises.
I will dive more into this. But maybe you guys have a good solution.