Accidentally bought a second copy of "Master Armorer VI" and I am unable to discard it.

(have a copy on my chocobo is why it let me buy it a 2nd time, I forgot I had it already ooops!)

I just want it removed from my inventory, a refund of Yellow scrip would be cool but not as important as getting rid of the un-discard-able item, I NEED MY SPACE!

Thanks for reading