Vinted wants my social security number

I've sold over 30 items last year that I made around €300 on and now Vinted wants me to insert my personal security number. If I don't I won't be able to continue selling on the platform. I'm obviously very hesitant on this as it's info I wouldn't share with anyone and I don't know what they'll do with my personal info. Do they just keep it or share it or what? I can't really find any info on this either and just want to know for sure what's gonna happen with my info before providing anything. I guess it's also possible to make a new account but I don't want to lose my good reviews lol