Order number vs. invoice number

I’ve got a problem with your order / invoice numbering system.
When I order a project, it is given a number in the form “2024-xxxxx”, whereby the five-digit number is chosen at random.
I then inform our accounting department of this number.
However, when the invoice arrives, it has a reference in the same format, but with a different number (obviously consecutive). I now have to look at each invoice and search for the original order number in the small print to assign it.
Would it be possible to use the same reference for the order and invoice? That would make the work much easier.
Greetings, Nils

Indeed, invoices and order number are not identical. Unfortunately, there is not much we can change about this at the moment. The invoice number has to be unique (legal requirement) and at the same time there can be multiple shipments per order, making a 1:1 relation impossible. We therefore note the order number on the invoice in addition.

Nevertheless, I completely understand the hassle here. We therefore offer the possibility to add a purchase order number. This number can be added on a quote (if required), but also to an order and will be dragged along so that your accounting department can make the connection. Does that solve your issue?

I have already tried the order number. I have to test whether our accounting department understands it.
Apart from that, it would also be nice if I received only one invoice for five orders placed at the same time, rather than five. Is there any way of doing this in your system?