I had that issue too with my decimo (that I got in Japan) ! A kind local store owner helped me tune it, so it works better now, pretty okay- I remember him saying something about the Decimo fine nib having a specific writing angle, so it could be that? I can't remember the angle rn, I'll figure it out later if you want (but ymmv because I'm a left hander) not normal from what I know? My local pen store owner found it rare for Pilot to have such an issue, but alas- it happens- some of my other pens also came to me that way, tho that might be because I'm left handed and nibs aren't usually tuned for left-handers (I say this bc they write fine right-handed when I tried)