Very Poor Service, Vodacom taking money

Our Business made a premature cancellation on a business cell phone contract in June 2017, all documantation required was sent to to the email address reqestedd as per the comunication from Vodacom. Additionally the settlement value required for the account to be closed was paid and the proof of payment provided to Vodacom. The monthly debits ceased and the phone number was never used again. To our surprise Vodacom started invoicing us again for the account in Feb this year, and continued to do so for months until I was able to cancel the . Vodacom never effected the cancellation, credit the account with the cancellation value paid, and then commenced billing once the account was no longer in credit. Vodacom not actioning the cancellation request aside, what has been an even more frustrating exercise is they now cancelled the account, but haven't paid back all the premiums which they debited on a account that was cancelled. After months of dealing with sandra.khoza and ignored emails all I get is the call has been logged? My last communication to her on the 11/10 has just been ignored it appears.