Hey, I remember seeing a thread on official thread about this, but I can't seem to find it. If I remember correctly, you have to ask a staff member. One of them will see your thread sooner or later
Hi, if this forum is anything like other forums I'm on, they probably won't be able to delete your account entirely because it can mess up the forum. It might be different for different forums, though.
You have to create a thread requesting it in the Ask The Staff section. Here is the thread laying down the rationale behind that decision.