Gnome shows ethernet connected when cable is unplugged

I'm trying to connect to the internet on my Debian 12 laptop using my phone connection through an USB-C cable. When the cable is connected and the connection sharing is activated on the phone, the Ethernet symbol shows up on the top bar of the desktop (Gnome 43.6). However, I cannot connect to any website from the laptop, although it's accessible from my phone. I tried to shut down and boot again with the cable unplugged, and now the Ethernet symbol shows up directly when booting. I still cannot connect when plugging the cable in again. I also can't connect through my phone's Wifi hotspot with the cable unplugged. Both Ethernet and Wifi have been regularly working between these two devices until now. I suspect Debian is stuck on some kind of old connection it cannot get rid of. What should I do?