Grand Master Helminter:
Anyone wishing to become a Palus Knight must have achieved at least level 20 and passed the appropriate test.
Your level is satisfactory, but you haven't passed the test to become a Palus Knight. Speak with Master Virgil in the Town of Gludio, pass his test, and accept the Gaze of Abyss as reward. Bring it to me and I'll transfer you to the Palus Knight class.