Default [Q] Root was successful on LG L40 but can't move app2sd card!

Hi XDA staff, I need some assistance here..
I have root my first android phone, LG L40 and it did sucess..

This is the instruction:
http://forum.xda-developers.com/show....php?t=2732311

This time, when I want to move whatsapp that is on Internal Storage with link2sd app, it says like this:
error notification

However the one that I pointed out makes me confused is on step 9 on the link that I have given..
It says that I can now plug in my sdcard, yet there is no instruction to unplug it..

My intuition was the step above that makes it error. I should've unplug it then plug it later.
Now, I am trying to re-format my sdcard with magic partition wizard.
Hope it works.

Sorry for my bad english