Grand Master Aldenia:
To become a Warrior, you need the appropriate level and token. Your level should be at least 20 to be qualified to change profession. To become a Warrior, you need the medallion of the Warrior to prove that you passed the Test of the Warrior, as well as an appropriate level. I am satisfied with your level, but it seems like you have not yet passed the Test of the Warrior. You will only be accepted as a true Warrior after you pass the test. Go ask Master Aymus in the village of Gludin about the Test of the Warrior.