I am in possession of 2 ids on codechef, by mistake, with 2 different email-ids. Could anyone please tell how to deactivate one of them. I only use this id and other one was made by mistake.
You could just delete it.
Login with the id you want to delete.
Go to edit profile >> privacy >> I don’t want to continue with Codechef.
Remember this is an irreversible action. Account will be permanently deleted.