After changing directory with website artifacts in .gitlab-ci.yml, 'GitLab Pages' show '404'

my .gitlab-ci.yml file was as follows:

pages:
    stage: deploy
 script:
    - mkdir .public
    - cp -r src/* .public
    - mv .public public
artifacts:
    paths:
       - public
  only:
    - master

and everything worked fine, the content of ‘src’ directory was deployed to .gitlab.io and was changing after every ‘git push’

I changed the line

- cp -r src/* .public 

to

- cp -r build/* .public 

and after ‘git push’, i see Error 404 (‘The page you’re looking for could not be found’)
CI Lint on https://gitlab.com/ci/lint for new version of my .gitlab-ci.yml shows ‘syntax is correct’
In ‘Pipelines’ i see status for last pipeline as ‘passed’ (green)
In ‘CI configuration’ on the project page I see my current .gitlab-ci.yml file

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And changing it back to old settings does not removes the problem, still ‘404’

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