You can't you need a forum moderator to do it.
Chat with our AI personalities
You will need to be a runescape member to post on forums, if you are a free user you can only browse them.
You need to have either a paid membership, or 5 million total experience points, to do that.
It is not possible to delete a RuneScape account.
There is currently no option to delete your RuneScape account.
You cannot send a complaint directly to Jagex, you can however post it in the "Rants" section of the runescape forums if you are non-member level 250+ or if you are simply a member.