Seduction succubus buff & duration bugged

First screen I cast ONLY seduction. The problem is that i dont have any idea how long is the debuff.

https://i.imgur.com/oG792cX.png


Second screen I cast seduction and AFTER any other spell, in this case CoE. The result i know exactly how long is the seduction

https://i.imgur.com/DPGlhfT.png

PROBLEM: I want to see the debuff of seduction and his duration when i cast ONLY seduction without any other spell / curse.

How can i do? :(

Do you know any others addons or something?

Ps. I forgot to say that the addon that I used on the screen is plate buff, and actually it works only if the seduction is NOT the first action made vs that target.