There is another user who posted the same a few days ago.
I have also been asked for a verification code to log in since a few days after seeing that post. So OP is not alone in this.
@JonRaymond or @Tanklet : Did BL or MW recently start requiring MFA even if users don’t explicitly choose it? Or is the verification code required only in some situations, such as users using VPN? If yes, then there probably should be an annoucement about it.
I am ok with mandatory MFA. In fact, with the new cashing-out option of exclusive points, it is a good idea for users to start using MFA anyway.