Worst Call Centre Agents

Worst Service, been waiting for delivery all day, i called the call centre at 16:00 hours and I was told the driver will be here slightly before 5, i called again at 16;45 as I have to leave the office, after holding for almost 15 mins, they hung up on me, I didn't know whether to wait at the office or leave, its really frustration to hold on the line for a long time only for someone to hang up just before u can say anything, i now had to call the call centre again to follow up, as i dont know if i should wait for the courier or i should leave, this service is pathetic, mind you, their call centre closes at 5, my ref no. RAIN04-***0 and called from ***. your agents are the worst, they could have answered and told me to wait or to leave but instead they hung up, n im now waiting on the line to get thru to call centre again