Welcome!

when adding a custom NPC it aint working.

I bet prayer got me banned easy. For a human being its impossible to reach such xp rates on chaos altar. Xp rates above 700k p/h are rearly to happen only when using 3rd party clients.

Little advice on what not to do: Speed offering. It got me banned yesterday for macroing. Its easy detectable as it works flawless with 700K+ xp rates p/h (dragon bones). Make sure you do the normal offering (which is way slower but less detectable) +- 400K xp p/h > human behaviour.