Whenever someone is searching for my name on Google they get my full birth date with year at the right side Google "knowledge panel". It is incredibly unnervin

Whenever someone is searching for my name on Google they get my full birth date with year at the right side Google "knowledge panel". It is incredibly unnerving to me. By what source do Google claim to know my exact birth date? The only way I can theoretically change this is if I "claim" this "knowledge panel" which involves sending more personal information to Google without guaranteeing anything.