We recently bought AnyConnect licenses:

but I can't create a license from the PAK, I receive following error message when I try:

I had a chat with support like the error message suggested, they confirmed the PAK is invalid and told me to contact the vendor.
The vendor told me I need to use the PAK to generate a license file, which I think I just tried without success... could anybody be so kind and tell me if I'm doing something wrong here? And if not, any suggestion how to proceed would be much appreciated.
Thanks :)
Marc