Hmmm. Booted a live version of Ubuntu off a USB stick and got the same result: No mounting of a thumbdrive on USB-C but it worked on USB-A. This is the second time I've had something like this happen with Ubuntu. I bought an X1 Gen 9 and the computer just stopped recognizing the battery. I was within the return period so I just sent it back and got the Gen 12. Now, I'm having a USB-C issue.
I haven't had any damage or physical issues that would explain a loss of the usb-c ports. Additionally, the ports still work to charge the computer, so they physically must be working (at least in some capacity). I'm stumped.
Edit: Now that I think about it, the only thing I can think of is that I recently bought a UGreen 65W power brick. It's the same wattage as my official lenovo charger. I wonder if that is behind it.

USB-C ports no longer sending/receiving data (Lenovo X1 carbon)
I have a Lenovo X1 Carbon Gen 12. The other day I noticed both of my USB-C ports are not receiving or sending data. External drives won't mount and my dock won't send signal to my monitor, but when I plug in my charging cable I am still getting power. When I use "lsblk" nothing shows up, even though sometimes I hear the chime signaling something has been plugged in (but it's inconsistent and sometimes doesn't chime).
Both of my USB-A ports are working properly and receive data, so it's only my USB-C ports.
I'm running Ubuntu 24.04.3. I tried to revert back to an earlier kernel in case that was the problem but it didn't fix the issue.
Anyone have a similar issue? Thanks!
Longer waiting time than to buy a gun. Smh.
The left has its voices, but I don't know many left-leaning people who hang on every word of media personalities. It seems less cult-ish.