Not so great customer service

I bought a second hand HP laptop. The delivery was quick, thanks for that. I have only one issue that left me dissatisfied. We agreed that I will get an upgraded RAM on my laptop as a discount trade-off. Before shipping, I was advised that the RAM upgrade was unsuccessful, then we agreed that it be abandoned (RAM upgrade). Gone is my discount. Upon receipt of my laptop, I discovered a few missing *****s on the back cover and some were loose. I reported that and I was told that the *****s were lost during the repair, which I was not told before shipment. I was told they could help source the *****s but then that's where it all ended to this moment. I am sure that cannot make me a satisfied customer. If you keep quiet they also keep quiet. When you talk, it's only then that they try to see your point of concern.