Hi, I just done my 4th job advancement. On the spot I used the triple throw 10 that is in my inventory, there is a message saying new skills added. But it did not appear in my skill tab, I thought this could be some bug that not appearing in skill tab so I relog and did not take the screenshot as my acknowledge is that triple throw 10 is 100% success learn. IGN : ShaMui
here is the screenshot of my current skill tab, and no I don't have the screenshot of the message as its 100% success skill.
Unfortunately without a screenshot I can't confirm that you used the skill book, but it sounds very odd that a skillbook would fail, indeed. Unrelated to this, I would urge you to update your files, as you are not using the latest files judging by your client name.
I uninstall older version then reinstall the whole client from the download link after the 31/1/2021 patch, did not do any changes once installed. And yeah triple throw 10 that obtained from Zakum drop suppose to just add the skill into your skill tab, yet it did not appear. The first thing come to my minds is that relog might solve the problem as it should be appear in skill tab once used. That's why I did not have the thought of taking screenshot of the message.
Unfortunately we are unable to refund this skillbook, but if it should happen again, please take a screenshot before and after, and we will do a thorough investigation. Apologies for the inconvenience.