500 Error when setting up a kubernetes cluster

When trying to set up a kubernetes cluster i am getting the below exception. I am using docker-gitlab CE [11.8.1]
I had set a cluster up previously, but when upgrading to the latest version of docker-gitlab I lost all my env settings and had to reset everything.
I believe this issue is because I may have changed my when readding the env variables

I have tried deleting all entries in the db which may encrypt using this but i am not sure what else i need to clean up

ArgumentError (key must be 32 bytes or longer):

app/services/clusters/create_service.rb:28:in create_cluster' app/services/clusters/create_service.rb:20:in execute’
app/controllers/clusters/clusters_controller.rb:109:in create_user' lib/gitlab/i18n.rb:55:in with_locale’
lib/gitlab/i18n.rb:61:in with_user_locale' app/controllers/application_controller.rb:423:in set_locale’
lib/gitlab/middleware/multipart.rb:103:in call' lib/gitlab/request_profiler/middleware.rb:16:in call’
lib/gitlab/middleware/go.rb:20:in call' lib/gitlab/etag_caching/middleware.rb:13:in call’
lib/gitlab/middleware/correlation_id.rb:16:in block in call' lib/gitlab/correlation_id.rb:15:in use_id’
lib/gitlab/middleware/correlation_id.rb:15:in call' lib/gitlab/middleware/read_only/controller.rb:40:in call’
lib/gitlab/middleware/read_only.rb:18:in call' lib/gitlab/middleware/basic_health_check.rb:25:in call’
lib/gitlab/request_context.rb:20:in call' lib/gitlab/metrics/requests_rack_middleware.rb:29:in call’
lib/gitlab/middleware/release_env.rb:13:in `call’

Fixed by increasing key length