Unsupported Media Type Error

Hi Adobe team,

I recently got accepted into the App Builder trial program and I'm trying to create a project from template however when I click the save button on my project it gives me the following error "Service getValidateAppName failed. Error code: 415 , Error message: Unsupported Media Type". This occurs even when I click save without changing any of the default parameters which are loaded up e.g. not adding extra workspaces and not changing the default app name and project title. Would very much appreciate any insights into this issue or potential solutions! 

**EDIT: It was a bug in production that occurs when the org doesn't yet exist as a publisher org in ARS. This ticket has already been resolved and the issue doesn't occur anymore. 

Thanks,

Geoffrey He