I talked to Klarna maybe 10 years ago. One of the things I wanted to know was how they dealt with abuse in Sweden, given you just need the social security number of a person and then you can do purchase as that person, and Swedish SSNs are not secret.
The friendly Klarna rep. had no idea what I meant, as you could only get stuff delivered to the address associated with the SSN. Based on how that would be abused in Denmark we suggested ordering a box of random sex toys to any random person in Sweden. The only answer I got was "Why would anyone do that?"
It took less than six month for Klarna to start asking us to block addresses, because they had no way to prevent abuse.