How to resolve Helm Error: UPGRADE FAILED: another operation (install/upgrade/rollback) is in progress

What happened

When deploying an application which contains Helm charts via KOTS, and the API pod restarts mid deployment, the underlying helm install/upgrade process would not have completed. Subsequent attempts to deploy the application will result in the following error:

Error: UPGRADE FAILED: another operation (install/upgrade/rollback) is in progress

How to solve it

  1. Manually rollback to the previous Helm revision:
helm history <release>
helm rollback <release> <previous stable revision>
  1. Re-deploy the desired application version from the admin console.