Git push tag not trigger CircleCI build

part of config.yml:

workflows:
  version: 2
  Test-Build-Deploy:
    jobs:
    - unittest
    - build:
        requires:
        - unittest
        filters:
          branches:
            only:
            - qa
            - dev
          tags:
            only: /^v[0-9]+(\.[0-9]+)*$/

when create a new branch and git push to github, CircleCi can trigger build,
but use command: git tag v0.4 && git push --tags origin on branch qa or dev, it can not trigger build???