https://ghostbin.com/paste/3yzo9

I need more information.

1.) What are the steps to reproduce this error?

2.) What version of spigot/craftbukkit are you using?

3.) Please put your config.yml and items.yml into a pastebin.com and link it.

From what I can tell from what you gave me is that it is a bug with TrainingPvP.

at me.jeroenhero123.TrainingPvP.CombatTagHook.isTagged(CombatTagHook.java:28) ~[?:?] at me.jeroenhero123.TrainingPvP.Commands.CommandRanked.onCommand(CommandRanked.java:53) ~[?:?]

As well as

Unhandled exception executing command 'ranked' in plugin TrainingPvP v7.3

Sorry I cant help much, you will have to contact the TrainingPvP developer.