If for any reason (bug or regression) you can't use the UI to delete a project from the Dashboard, please try the following:
We provide a robust command line interface to Haiku as a Node package. See here for instructions to install: https://www.npmjs.com/package/@haiku/cli
Once you have it, you can use
haiku login to log in,
haiku list to list your team’s projects, and
haiku delete <ProjectName> to delete your project by name.