As you can see in the pics, this bow (and it's the only thing in my inventory doing this) is broken. Seems you as usual broke something with an update... I have no idea what name it is but I think I got it in that recent Festival. I know I haven't had it long. But as you can see from the pics, it's name is missing and so is the description of what it's built in "power" is (between the upgrade bars and my equipped runes). I already forgot what that bow does lol... and now i cant' tell. I tried saving the game and rebooting the ps4, idk why i thought that would help but of course it didn't. I thought it might have to do with the update and being one of the bow's equipped in my sets, but the other bows still have their names, as does my armor and w/e else... In fact, I've sure I've got everything in the game before finishing the Ireland and France DLC's, and I just checked all my armor and weapons. nothing else is screwed up.
The first pic is from my inventory, the 2nd pic is from the Blacksmith's "change appearance" tab so you can actually see the bow in question (it's like grey wood with greenish vines on it and flowers...). If you can tell, in that pic my cursor is also hovering on the blue version of the bow, and it's name is missing on the screen there as well.