Extremely slow service and unable to cancel

I'm not someone who normally complains but tonight I'm giving this a one start because zero isn't possible. A simple dessert order at 19:30 ended up being delivered after 21:00. Three drivers cancelled the trip. I tried to cancel the order but was told i was going to have to pay as the order was ready. Driver confirmed chocolate pie was going to take a further 20mins and really, that sounds like it hadn't even been started. Uber contact agent was only available to chat once the order was on its way. Chocolate pie was burnt and the whole experience left a bad taste. Will think twice before ordering again.