Hi Britta,
Hope you are well!
Could you please elaborate how do you want to display the invoice numbers in the report? Also, you can try to group the report by invoice number to display the data.
I understand your perspective and apologize for any inconvenience you faced with the reporting. I suggest you to post this as an Idea/feedback for our product team by going to Cvent Community > Participate > Product Ideas.
We encourage you to always submit your ideas or any challenges you face while working with the product. As it also help our Product Development team to review the possibilities and if it works we may try to incorporate such changes in our future releases.
------------------------------
Raashi Semwal Khati
Senior Quality Analyst
Cvent
------------------------------