Mount Snowy Gryphon

The Problem: 

my char Asu Hunter  have already purchased the Snowy Gryphon mount in Dalaran, and I have also purchased the Flight Master's License. However, I still cannot fly using the mount, even though it should be capable of flying.

Could you please help me resolve this issue?

How it should work: 

How to reproduce:

Character the bug occurred on:

To fly in northrend (dalaran, etc) you need to learn the Cold Weather Flying. 
Flight Master's License is only for outside Northrend.
Please kindly read the spells information, i think there are no problems or issue on things you described.

not an issue.