Pam's Song

I bought one, here's what happened:

So my Karstan is 112 att U/H I hammer it buy a Pams Song use the Spirit thing to scroll it, used 50% it worked used another 50% it worked...Pam Son still not used, lucky me.

Next I move on too my 57 ATT Bracer U/H, I hammered it equip it use a 50% worked use another 50% it worked...Wow lucky me again.

Now, I move on to my 125 att Metus U/H I hammered it used a 50% it worked used the next 50% it failed, asked me if I wanna use it I say yes he pops up behind me plays a song and I still have my slot.

So, I'm happy I got hammer 3 items and it failed on the last weapon I wanted to hammer.

Did Pam's Song go poof after it was used?