I have Fishing Expertise Lv14 & Reeling/Pumping Lv16 that's 2 lvl higher than my Fishing Expertise but I get Penalty on dmg although this happen only if your Reeling/Pumping is 3 lvl's higher than your Expertise which is not the case, this is obviously a bug of this server, as u can see in the pic above the difference is 2 lvl's & I get msg that I have 3 or more lvl difference so yeah what is obvious it's obvious this thing need fixing.
