[NAME]  Happy to help.  In that case since you've observed this behavior with multiple adapters, it may be an issue with the USB-C port itself.  If you haven't already, I'd suggest updating the BIOS on the system.  If that doesn't solve it, then convincing Dell that this is a port problem might be tricky.  If you have a way to connect something like a flash drive to that USB-C port, that might be another data point if you can establish that the port is "flapping" even with a completely different kind of device plugged in, and a flash drive would exhibit similar behavior of disappearing and reappearing in that case.  Out of curiosity, do you hear the Windows sounds for a device being disconnected and reconnected when this happens?Purely in the interest of expediency, a USB-A "regular USB" to Ethernet adapter might be the best option at least in the immediate term if you need working Ethernet connectivity immediately.  They're not expensive, and it would certainly be less painful than dealing with warranty service on your system even if Dell Support goes for it.  If you only have mail-in warranty coverage rather than on-site service, that's even more true.  But I also completely get that what you've already spent money on should be working properly and that if there's a problem with that port, you'd want it fixed.  So I'm not suggesting the USB-A adapter as a permanent workaround, just something that's likely to succeed in case you'd need to wait until another time to keep working with Dell Support and deal with system service.
I called Dell support to troubleshoot a Thunderbolt 4 USB Type-C to Ethernet adapter problem. The wired network randomly disconnects every 10-45 minutes. The agent told me the laptop does not support this adapter and should use a regular USB to Ethernet adapter. I have tried 2 different adapters with the same result. The first one is a Dell branded dongle I purchased directly from Dell. Fearing a part failure I bought another from Best Buy. I'm convinced it's not a dongle problem. My biggest issue here is the laptop (6 months old) support for such a trivial device. Was the agent feeding me some simple "not supported" answer to close the ticket? Should Thunderbolt 4 USB Type-C to Ethernet be a supported configuration for this laptop? Is there something wrong with the hardware here? Workarounds? I'm at wits end with Dell right now. Thanks
Inspiron 7506 USB-C to Ethernet problem