vercel: "Error! Your deployment failed. Please retry later."

As of version 16.1.1, my deployments have started failing with:

> Error! Your deployment failed. Please retry later. More: https://err.sh/now-cli/deployment-error

I’m unable to see any further error information, so it’s difficult to fix!

Here’s my now.json:

{
  "version": 2,
  "builds": [
    { "src": "next.config.js", "use": "@now/next" },
    { "src": "dist/*", "use": "@now/static", "config": { "distDir": "output" } }
  ],
  "routes": [
    {
      "src": "^/s(?<season>[0-9]+)/e(?<episode>[0-9]+)/(?<time>.+)",
      "dest": "/index?season=$season&episode=$episode&time=$time"
    },
    {
      "src": "^/s(?<season>[0-9]+)/e(?<episode>[0-9]+)",
      "dest": "/index?season=$season&episode=$episode"
    },
    {
      "src": "^/s(?<season>[0-9]+)",
      "dest": "/index?season=$season"
    }
  ]
}