Warranty dispute resolution

My laptop was purchased in October of 2022, and about 6 months ago it just stopped turning on, black screen. The warranty is the basic plan so I sent it in to be repaired and a week later I received it back in the same condition. The letter stated that dell emailed me about what needed to be done and I denied it, which is completely false. So I called support which was a complete disaster, saying that the laptop was wet when they received it. Complete fabrication. What are my options to find a resolution to this. Computer was less than 7 months old when it stopped working I send it in to get fixed they send it back without any communication, but lie saying they did, then they try and sell me a service for $50 that will let me send it back and they will tell me what is wrong with it and how much more it's going to cost to fix. It's still under warranty. Is this normally how Dell operates? How can I escalate the issue?