Plugin remove stale torrents Error connecting to transmission: Network is unreachable

Hello, I am a Chinese user, using the from_transmission plugin prompts the following error.

2020-09-17 08:06:31 INFO     manager                       Test mode, creating a copy from database ...
2020-09-17 08:06:31 INFO     manager                       Test database created
2020-09-17 08:06:33 VERBOSE  task_queue                    There are 1 tasks to execute. Shutdown will commence when they have completed.
2020-09-17 08:06:33 INFO     transmission  remove stale torrents Trying to connect to transmission...
2020-09-17 08:06:33 CRITICAL plugin        remove stale torrents Error connecting to transmission: Network is unreachable
2020-09-17 08:06:33 WARNING  task          remove stale torrents Aborting task (plugin: transmission)
2020-09-17 08:06:34 INFO     manager                       Removed test database

here’s the congfig.yml:

templates:
  tr:
    transmission:
      path: /data
      host: localhost
      port: 9091
      username: myusername
      password: mypassword

tasks:
  HD dolby:
    rss:
      url: https://www.xxx.com
    accept_all: yes

    free_space:
      path: /data
      space: 10240

    seen: local

    content_size:
      min: 1000
      max: 51200
      strict: no

    download: /data/t

    template: tr
tasks:
  remove stale torrents:
    from_transmission:
      host: localhost
      port: 9091
      username: myusername
      password: mypassword
    disable: [seen, seen_info_hash]
    if:
      - transmission_date_done > now - timedelta(days=3): reject
    transmission:
      host: localhost
      port: 9099
      username: hacker2k
      password: *****
      action: purge