Aslam u alikum

from last three days my yahoo blocked today I more try to open my id, than Yahoo give us the following instructions:
Customer Care

Please follow these steps to change your password.
1. Call 1(800) 730-2669
2. Provide reference number ****** to the representative so that they may assist you faster.
3. A representative will confirm your Yahoo username: ******

I don't know where I should use Referenc or incident number ???
if someone know kindly guide me