Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Total Waste of Money!!!!

I registered for this pump. It worked great for about 2 weeks, then the suction just stopped. I called customer service and they sent a new one out right away, but other things began to fail. The milk backs up in the valves and I have to bang the unit on the sink to get the milk to fall through to the bottle. If you don't, the milk backs up into the unit and leaks out where the a/c adapter connects, potentially causing other seious problems. Please do not buy this pump!