A player got hit by a windcaller and received "levitation 9" and flew upwards without end. The clear command did not remove it, and the timer was 0 seconds. Player passed y= 3500. I had to force tp the player into solid rock to stop this via death. This was with the Blutmond modpack with no alterations.

No longer relevant, windcaller rewritten

Windcallers by default do not give their targets levitation 9 nor for a lengthy duration, most likely is some kind of mod affecting levitation application.