Help with Zigbee2MQTT Issues: Add-On Won't Start, Original Port /dev/ttyACM0 Missing

Hello everyone,

I am desperate. About 3–4 weeks ago, my Zigbee2Mqtt integration suddenly stopped working, and I can no longer control my Zigbee devices.
The add-on won’t start anymore. I’ve searched all forums for a solution, but nothing has helped.
I’ve reflashed my Sonoff Zigbee dongle, reinstalled Z2M, and checked the settings of my Virtual Box. Nothing worked.

Zigbee2MQTT: Version 1.42.0-2
Sonoff Dongle: Tried several firmware versions. Currently using 7.4.1.0 - 115200

When starting Z2M, I get the following error message:

[2024-12-29 22:31:54] error: 	zh:ember:uart:ash: Failed to init port with error Error: Error: Operation not permitted, cannot open /dev/bus/usb/001/004  
[2024-12-29 22:31:54] error: 	z2m: Error while starting zigbee-herdsman  
[2024-12-29 22:31:54] error: 	z2m: Failed to start zigbee  
[2024-12-29 22:31:54] error: 	z2m: Check https://www.zigbee2mqtt.io/guide/installation/20_zigbee2mqtt-fails-to-start.html for possible solutions  
[2024-12-29 22:31:54] error: 	z2m: Exiting...  
[2024-12-29 22:31:54] error: 	z2m: Error: Failed to start EZSP layer with status=HOST_FATAL_ERROR.  

The current Z2M configuration looks like this:
port: /dev/bus/usb/001/004
adapter: ember

I’m unsure about the port /dev/bus/usb/001/004. Initially, the port was set to /dev/ttyACM0 and the adapter to ezsp.
Some posts suggested flashing the Zigbee dongle and using ember instead. I followed this advice, but it didn’t work.

The Zigbee dongle is shown in Home Assistant under the path /dev/bus/usb/001/004, meaning Home Assistant has access to the dongle.
However, in forums, I’ve only ever seen paths like /dev/tty*. Could the path displayed be correct?

When I search for tty* under hardware, I only get the following results:
image

Where has the original path /dev/ttyACM0 gone, and why is it no longer visible?

Can anyone help me get Zigbee working again?