Can't speak to an agent to follow-up or cancel orders.

I have been a customer with MWEB for almost 10 years and have never had any issues until now. I have moved home where there is fibre available and ordered it online through my account. I then missed a call from Mweb and was told to call the sales number. I have tried doing this and selected the follow-up option but there was no option after that to speak to an agent. I then called the sales team who also put me through to the same number. Having spent ages on hold, and after numerous phone calls, I want to cancel the order and will go to a different provider. But guess what, I can't get through to an agent to cancel it! I try the sales team who put me through to yet another line with options that take me to a dead end or I end up sitting on hold. This is appalling customer service from a company that I used to praise about.