15rp reward battles

So I know that to get 15RP you need to defeat an opponent at least 10 levels higher than you but how can you even get such fights ? I'm level 21 and only get opponents from lvl 16 to 24 when I search for one ?

Don't search that hard for higher level players to attack! The 15 rank point doesn't work... Yeah they probably thought about adding something like that, but I really haven't seen anyone getting 15 rank points at all! It's always 10! I think they changed it because if they let a big variety of levels to attack each other, higher leveled players, would be able to attack lower leveled ones with half their party (so less stamina used - less wines), and lower leveled players wouldn't be able to defend medals or ranking at all!