I can reproduce it just by using chat command / macro.
- Be on Vengance. Invoke “/cast Sigil of Flame”
- Switch to Havoc. Invoke “/cast Sigil of Flame”
- Come back to Vengance. Spell not learn when “/cast Sigil of Flame”.
Sigil of Flame is a different spell for Havoc and Vengance. It has different ID. Maybe this is part of the problem.
Can you reproduce this issue? Or it’s only my set-up?