score:4
OK I just found an answer to my own question. It seems that they don't think my two-letter last name is a valid one!!!
I added three spaces before my last name and it worked for the system!
Such weird bug!
~~~~update on 20 Dec 2021~~~~
They just confirmed that my insurance contract will be cancelled:
Dear Sir/Madam
As requested, we have cancelled the policy number XXXXX
The policy has been cancelled and the amount of the prime will be refund in the 30 days to your credit card that was used to make the booking,
Regards,
AXA SCHENGEN