New HA server, was working, now lone Zigbee entity is unavailable

I set up a new HA server using the vBox and VMDK approach, and I’m using a HUSBZB-1 for Zwave and Zigbee. I have three test devices, 2 Zwave switches and 1 Zigbee light bulb.

Everything was working fine, I had all three detected and was able to turn things on and off.

Well, I recently came back to the installation to experiment and the Zigbee bulb shows in Entities as unavailable. I can’t figure out what’s wrong. I don’t see a log for it. What are the troubleshooting steps for Zigbee entities?

There’s not much in my configuration.yaml.

# Configure a default setup of Home Assistant (frontend, api, etc)
default_config:

# Uncomment this if you are using SSL/TLS, running in Docker container, etc.
# http:
#   base_url: example.duckdns.org:8123

# Text to speech
tts:
  - platform: google_translate

group: !include groups.yaml
automation: !include automations.yaml
script: !include scripts.yaml
scene: !include scenes.yaml

# Zwave config
zwave:
  usb_path: /dev/ttyUSB0

# Zigbee config
zha:
  usb_path: /dev/ttyUSB1
  database_path: /config/zigbee.db

# Time & Date Sensor
# Example configuration.yaml entry
sensor:
  - platform: time_date
    display_options:
      - 'time'
      - 'date'
      - 'date_time'
      - 'date_time_utc'
      - 'date_time_iso'
      - 'time_date'
      - 'time_utc'
      - 'beat'

I must be getting interference. When I put the device next to the HUSBZB-1 it works.