No Service or feedback received from Vuma and SADV

Vumatel and SADV is by far the worst service provider in the history if fibre services... I had to change my banking details and contact number due to some personal issues abd as a result my fibre premium was delayed. I had since made contact with SADV and Vuma on various platforms, emails and whatsapp to reuqest a payment link for my fibre to be activated. 2nd March was my first request, to this date 8th,no link was supp****. I have numerous whatsapp messages and emails requesting my services to be cancelled and my premises cleared, but I am receiving no joy or service. I would like to apply with an alternative service provider, whom I believe will be able to provide me an actual service. How long can it take for a subscription to be cancelled?