I am facing the same issue as well, and they told me that is my service provider problem
Have you submit the ticket to Blizzard too ?

We are not the only affected users:

http://us.battle.net/d3/en/forum/topic/9972468124

yea, im using hotlink actually.
then i have no choice to tag my gf phone number (Digi) in my Bnet account

glad to know that.
which telco you are using ?

you may submit a ticket and request for an escalation, since the issue is persists about 2 weeks already.

mine 1 is 016 which is converted to Hotlink at few years ago, and it has no problem.
while my another hotlink number 011-1* has the problem.

read some comments by the forumer, its very funny that the customer support refuse to solve the issue, and keep asking user to check with the telco.

http://us.battle.net/d3/en/forum/topic/9972468124