google cloud billing API: not able to update billing info

Question

I am trying to learn how to use the cloud billing API and playing around with it's methods. I copied a code snippet in Java that shows how to use the updateBillingInfo method. I have a project in my cloud account, and it has a billing account associated with it, and I wanted to change it to a different billing account. Here's what I tried:

String name = "projects/My project";
ProjectBillingInfo info = new ProjectBillingInfo();
info.setBillingAccountName("billingAccounts/$BILLING_ID");
Cloudbilling.Projects.UpdateBillingInfo request = cloudbillingService.projects().updateBillingInfo(name, info);
ProjectBillingInfo response = request.execute();

and my problem is that request.execute() (as well as the API browser explorer) throws an exception with code "500 - internal error encountered". Am I not using it correctly? It was my understanding that after this, when I check my project in GCP, I should see my project listed to the new billing account. Help is much appreciated.

Answer 1

You are using an invalid Project ID, since GCP project IDs have no spaces in them. Note that Project IDs and Project names are different things. It needs to be the ID as seen here. The rest of your code snippet seems fine, just make sure you put the actual project ID like this: projects/your-project-id