if i make a login from the shell with "sudo docker login myownregistry.com, then login success.
unauthorized to access repository
This error suggests the login was successful, but the account you are using has insufficient permission to push the image. If the login failed you would see a login error message in the log output in the user interface.
another thing you can do is make sure the secrets are configured correctly and are being used to populate the username and password fields. If username and password are not being populated by secrets you would see an entry in the log output indicating the step is running in guest mode.
This is what missing credentials and guest mode looks like:
If you find this is a problem with secrets, we provide a troubleshooting guide that describes common problems. The guide also provide instructions for the additional information that should be provided to receive support.