Running gitlab-ci with volumes on gitlab.com

Hi,
I am currently testing a group of images in the CI part of gitlab (with the gitlab.com free version) as a test. My group of images use volumes and the test is working well on an EC2 instance. It doesn’t seem to work when I run it with Gitlab-CI. I used a little bit my GoogleFu (I am green belt) and it seems it is not possible to use volumes except if you specify them in the runner definition which means self managed and I suppose volumes alway present. I just need the volumes for the test.
Here is the YAML part :

main_test_1:
  stage: main_test
  image: docker:stable
  services:
    - docker:dind
  script:
    - mkdir scio_data
    - mkdir scio_input
    - mkdir scio_data/test
    - mkdir scio_data/test/PEP1
    - mkdir scio_results
    - cp Main_Tests/test_1/data/DN?.pdf scio_data/test
    - docker login -u gitlab-ci-token -p $CI_JOB_TOKEN registry.gitlab.com
    - docker pull $CONTAINER_TEST_IMAGE
    - docker pull $CONTAINER_MLE_IMAGE
    - docker pull $CONTAINER_POSTGRES_IMAGE
    - docker volume create --name code
    - docker run -d -v code:/code $CONTAINER_TEST_IMAGE
    - > 
        docker run -d -v code:/scio_work/bin  
        -v ${PWD}/scio_input:/scio_work/input 
        -v ${PWD}/scio_data:/scio_work/data  
        -v ${PWD}/scio_results:/scio_work/tmp 
        $CONTAINER_MLE_IMAGE "bin/run_test.sh"
  except:
    variables:
      - $MAIN_TEST_DISABLED

It says I don’t have the rights to run bin/run_test.sh
I have them when running on an EC2 instance.

Thanks in advance
Bruno