I am level 30 and I have completed all the learn to fly missions but the level 30 one does not appear to me I have gone to look for that character to accept the mission and it does not tell me anything.
Check if You don't have flying scroll first to use in inventory. And check again if You did all the missions step-by-step. You can also take a look in quest list, and remove any quest with Flying if You got any, and take again.