Frequency: Sometimes

Character Name: Qoo Kitty

World: Tonberry

Steps:
1. Cast Fire I at Monster A, before finish casting, get another teammate to kill off the Monster A.
2. If your Fire I is canceled with the word interrupted
3. Try to cast a few Fire I at Monster B, your next few cast will be canceled with the word interrupted non stop.

Experienced this problem only since patch 2.3.