Invoice number is not in order

Good day, sng.

Let me assist you regarding the invoice number.

I'd like to know first if you're referring to a report that shows the invoices like the Invoice List. Though we can sort this report by ascending or descending order, it's only for the transaction date.

If you're on the Invoices page, we can click the arrow the No. That way, we can arrange the numbering. Refer to the screenshot below:

Also, you can set your own numbering preference. Here are the detailed steps on how to how to change the invoice number on sales forms.

Keep on posting here if you need more help. Stay safe!