First, check your rescue email account. If you asked that it come to your regular account, then check in your Spam folder. It can take several hours to get a reply.
The Three Best Alternatives for Security Questions and Rescue Mail
1. Send Apple an email request at: Apple - Support - iTunes Store - Contact Us.
2. Call Apple Support in your country: Customer Service: Contact Apple support.
A substitute for using the security questions is to use 2-step verification: