I don't get the notifications when I'm "subscribed" to a topic.
Is there something that can be done?

Keep in mind that notifications don't go to your display email, which is the email you have set to show up in your profile. (In your case, your Yahoo email.)

Instead, they go to your account email, which is the email address that you used when creating the account.

If you no longer have access to that email, you'll need to change your account email in your profile to an address to which you do have access, in order to receive notifications. Just remember that while your display email can be anything, your account email cannot be a free email service like Yahoo.