Serial number wrong after system board replacement

[mindlight]

TLDR: I need to change the serial number to be able to work.


My laptop broke and I sent it in for repairs. However, when I got it back a week ago 2 of the programs I work in didn't start. Missing license key.
I contacted the vendor and according to them it could have been caused by corrupt harddisk (I was desperate and was open for any solution). So I swapped out the SSD and installed a clean one and installed Windows 11 and that's when weird things happened.
Windows 11 Setup, after getting internet access, claimed that my computer was enrolled to German company.
This got me thinking. I went into BIOS and Serial number was not the one on the label on the laptop.
I contacted the German company and while they were unable (unwilling?) to verify that they had sent
in a similar laptop for repairs they told me that the model I have is one of the older ones they use.

I contacted the vendor of the software I use again and they told me that they tie the license key to the serial number and some MS number among other things.

So, I contacted the repair shop and while they were unwilling to acknowledge that they had forgotten to
reset serial etc they asked me to send in my laptop so that they could fix it.

My problem is that I have been unable to work for 3 weeks and while my customers are somewhat understanding this kills my business.
I will send it in in two three weeks but I can't do it right now.

Is there a way of changing the serial number on a HP Elite X2 1012 ?
There is no BIOS passwords or anything.