Account Cancellation

I am trying to cancel my account because am being retrenched and i won't afford it anymore, initially i was cancelling it because of the bad network and am still waiting for a technician to come and check so the account can be cancelled. Now i have a new reason for cancelling it, which is loss of income. But you guys are still taking money from me. And am yet to receive an invoice for my account, haven't even received one invoice.