MiWay Not Treating Customers Fairly

I have recently taken Miway vehicle insurance (a few weeks ago) and I am already starting to regret having joined this company. I have been trying in vain to get through someone at the customer services department to make an amendment on my policy, but have not been able to get through their call centre at all. Everytime I call, I have to hold on for more than 20 mins at a time and eventually have to hang up because I either run out of airtime or have to attend to my work duties. Surely it is not acceptable for a customer to wait this long to discuss a very simple query? And I would understand if the call centre is experiencing high call volumes on certain days, but if this was the same experience on more than 4 occasions, then surely something is wrong with their processes. I have tried calling the sales channel and my call is answered within 10 seconds, which is great, but then I am speaking to someone who can only sell me a new policy. It is clearly evident where Miway is prioritising its resources. So come on Miway, how exactly are you 'treating your customers fairly', if you do not even provide your customers with channels to contact you and make post-sale changes?