Changing E-Mail Address!

My Norton Account has an old E-Mail address, no longar used.  (360 v5)

When I try to change this to my New E-Mail address I am informed "an account already exists with this E-Mail account" Sure enough when I check in under the new E-Mail

address an account indeed exists, although it is empty and has been established sometime,

this obviously needs to be cancelled,  how does one do this .  I have previously telephoned

re. this but nothing has happened, even though I was asssured empty account would be

cancelled