problem working with the theme OneUI 3.1 by pixelcave

My backend is play framework and my front end is angularjs. When run from play gives an error

warning: Task “dist” not found. Use --force to continue.

Aborted due to warnings.
— (Running the application, auto-reloading is enabled) —

[error] p.c.s.NettyServer - Failed to listen for HTTP on /!
[error] (compile:run) play.runsupport.ServerStartException

how do I resolve it?

Better to contact the author