Standard checkout demo code reports "TypeError: body used already"

[PaulHeft]

I am running the standard checkout demo code from https://developer.paypal.com/integration-builder/. When I click on a payment button (PayPal, or Debit or Credit Card), server.js reports:
Failed to create order: TypeError: body used already for: https://api-m.sandbox.paypal.com/v2/checkout/orders

Any idea what I'm doing wrong?

Thanks!

[PaulHeft · Accepted solution]

This error is no longer recurring. Please ignore!