It seems to you got control of your account again.
If you want Jagex to investigate your Hijack then use the advice Runefloors came with , this will not bring your stuff back and you will not be informed by their findings, but they will look into it and do what ever they do with scumbags like them
I would really suggest you to look into support page's :
Securing your Computer/Device and Account. Keeping your email secure (Just in case)
Did you have a Bank pin for your in-game wealth ?
I know you didn't have Auth set up for your RS account.Clan : Order Of Adventurers