Shaik Sufyan from Dell finally solved the issue today. He was amazing, unlike the other Dell representatives. Thanks. 
I have ordered a Dell XPS computer and a monitor from Dell on behalf of the University of California, Santa Barbara. The computer was always overheating and within a week, one RAM died and the computer didn't start. I talked to customer care and initiated the return. I have returned those packages, and I printed RMA on those very clearly with big fonts. And the FedEx guys picked up the computer and the monitor & put the call tags in front of me. There is no chance that the tracking could be wrong, I double-checked for both. Now FedEx tracking shows that both the order have been delivered.  But Dell is claiming that they did not receive the Desktop. They received something else in the box. What type of embarrassment is this? You first send a faulty computer and then you don't even refund it. It is not my money, it is UCSB's money, it's government money. I am a Ph.D. student and Dell's activity is going to ruin me now. It is Dell who chose FedEx, it is their responsibility, not mine. I definitely sent the desktop. Either the FedEx staff or the Dell staff stole it. Who will be responsible now? What can I do? I am completely devasted purchasing a Dell computer. Worst company with worst customer satisfaction. Please do something asap.Your Return Authorization Number :Order : RMA : Pickup Date : 07/13/2021  Pickup Tracking :  Order : RMA : Pickup Date : 07/13/2021  Pickup Tracking :     
Dell XPS died in one week, returned it but no refund issued