poor service

Why is difficult to convert my expired contract to 'pay as go'. On 29 July I contacted the call centre to convert my two cell accounts to pay as you go but the call centre agent was of no help. I was transferred to cancellations dept and was put on hold for almost 24min and had to cut the call. I then sent an email to process my request and received an email 2 days later confirming my request has been processed (ref no.748733). This morning I receive a bill for July services on my accounts (WHY?). I attempted to contact the call centre but was on hold for 15min on first attempt and 16min the 2nd attempt. When I finally got through to an agent, I was cut off during the call.