Customer support chat with wait time/period to speak to a actual jagex employee. Like my case. My account was banned for botting and has 2 major offenses on it. The funny part is that I recovered my account after it being hacked. A few days after recovering it got permanently banned. I haven’t had access to this account since 2017, Hense why the botting should be removed from my account. It just doesn’t make any sense. But here we are in 2019.
We absolutely would quash a ban incurred by a hijacker, have you tried appealing it here? https://support.runescape.com/hc/en-gb/articles/115002238729-Account-Bans