The same thing happened to me. I never received a reply from accounthelp@jagex but after about a month the registered email on my account was reset to none and I was able to use my recovery questions to recover my account.
I used to be in Guardians of fate, a DK/ Monster killing clan and I quit for a few years and now it looks like they are no longer active so I need a new clan to refresh my memory of DK and various oter Monster killings. My levels are 85 Atk/Str/Def 76 Prayer 91 Mage 79 Range 89 HP