Cant Clear Mark net

Hi,

I have accidently Mark Net some of the metal that have short connection. I used ctrl+c to terminate the process. Then somehow when i tried to UnMarkNet those net nothing happen. It couldn't be remove unless i restart my cadence.
I used cadence IC 6.1.7. Let me know if you guys have any solution on this whether by using Skill to refresh the database or any method might help.

Thanks,
Adam