Unable to delete domain

[ivailosim]

Hello, I am trying to delete my domain(s) lastjourney.tk (and www.lastjourney.tk) and I keep receiving error messages as follows:

For lastjourney.tk: "Error:Before the system can remove the parked domain “lastjourney.tk”, you must remove the following subdomain: “www.lastjourney.tk”

For www.lastjourney.tk: "Error:The system cannot change the master entry www."

Please help, I need these domains removed.

Thank you!