Security question against hackers.

If you guys saw my intro, then you all know my story. I got hacked. I'm about to make a new character and get right back up on my feats. Now my question is: This hacker that deleted my characters. could he be aware of me making a new character? Someone said i should change my routers password and i would also like to change my ip. Someone on youtube asked me for my characters name. He was saying he would help me. Show me how to combo. And i later found out about traces of hacks on hes channel. And on hes friends channel. Hes youtube user name is shmuck97. I had 2 characters. 1 on 2 seperate accounts. So i figured. It couldn't have been someone on Dungeon And Fighter beccause they would have only deleted 1 character and could not get to the seccond character. Then it must be him. It was just some hours after i gave him the names that my characters vanished. So to delete a character, does it only require the name of that character? Or is he on my computer somehow and can delete anny new character i make on a new account and that i should change my routers password and change my ip. Please provide help.

A miracle has hapened. I think my ticket sent to Nexon got through and my characters have been restored. I will re-introduce myself in the introduction section.