How to re-cast Sage's Elemental Change on the same monster

[CyanZoldyck 0]

Hi! Just needing some advise/help or maybe some of your codes on how I can re-cast Professor's Elemental Change Skill on the same target? I'm talking about casting it on Players.

 

I've already enabled the Elemental Change on Players however, once I changed their Element for example to water, I can't change their element anymore.

I really need this for PvP.

Thank you so much!