I am getting below error

Running with gitlab-runner 14.0.0 (3b6f852e)
  on gitlab-runner-artefactory-gitlab-runner-68f94fd89-pnd6g DaN3U_2T
Preparing the "kubernetes" executor
00:00
Using Kubernetes namespace: sai
Using Kubernetes executor with image aie-docker-dev-mydockerrepo/python:3.6-strech ...
Using attach strategy to execute scripts...
Preparing environment
00:06
Waiting for pod sai/runner-dan3u2t-project-9879-concurrent-0zdmgf to be running, status is Pending
Waiting for pod sai/runner-dan3u2t-project-9879-concurrent-0zdmgf to be running, status is Pending
	ContainersNotReady: "containers with unready status: [build helper svc-0]"
	ContainersNotReady: "containers with unready status: [build helper svc-0]"
WARNING: Failed to pull image with policy "": image pull failed: Back-off pulling image "aie-docker-dev-mydockerrepo/python:3.6-strech"
ERROR: Job failed (system failure): prepare environment: waiting for pod running: pulling image "aie-docker-dev-mydockerrepo/python:3.6-strech": image pull failed: Back-off pulling image "aie-docker-dev-mydockerrepo/python:3.6-strech". Check https://docs.gitlab.com/runner/shells/index.html#shell-profile-loading for more information

I am trying to run job using gitlab runner. What could be the possible reason for failure ? I figured out ImagePullSecret could be set but I am not sure where to use that ? Anyone having idea ?