I don’t know. Until a couple of days ago, there were no Dracthyr below level 60.
There have been problems with flying since the patch. Blizzard are on it, but as always with a new patch, expect some glitches:
So all I can do is suggest some questions to ask.
There is a button called Skyriding just right of center on the top bar of your mounts page. It is meant to allow you to toggle betwen skyriding and regular flight. Can you do something with that?
Are you levelling through Dragonflight? Have you done the Dragonflying quest chain yet?