Spawn server error

I start a new server on Jupyterhub, and get this errer below:
Error: HTTP 500: nternal Server Error (Error in Authenticator.pre spawn start: TypeError unsupported operandtype(s) for +: ‘NoneType’ and ‘list’)

hub use dockerspawner, and no container is started when this error comes, the image I use is the custom jupyter image which I custom the to change the gid and uid
Any help would be appreciated

Please could you give us enough information to reproduce your error? For example, your versions of JupyterHub and other components, how you’ve installed everything, your config files, etc?