Text codes might be the result of someone with a similar username or email address trying to sign in to their account but mistyping your username or email address instead.
When a sign in fails because the password does not match, the user might try to reset the password, but if they are mistakenly trying to sign in to your account, the security codes necessary would be sent to your text number or email instead of theirs.
Or if you have 2-factor authentication enabled, the codes might be sent automatically due to the sign-in attempts.
As long as no one else can see the codes but you, no one else can reset your password but you. Which is why the message says not to share the code with anyone.
