Apple Account profile picture changes mom's contact photo on inherited iPhone

my mom gave me her old phone, wiped it, and logged in with mine. now whenever i change my profile picture it changes her pfp in my contacts and for some reason, my phone thinks im my mom.

since its my moms old phone, for some reason it thinks its my mom. when i say " hey siri, whats my name " she replies "mom" and i also recently changed my apple id pfp to some random thing and it did the same thing with my moms in my contacts. its weird.

[Re-Titled by Moderator]