Can't change algorithm

Run the supplied jwt.sign reproduction first, then trace the call through node_modules/jsonwebtoken/sign.js, node_modules/jws/lib/sign-stream.js, and node_modules/jwa/index.js. Compare the ES256 and README RS256 cases, including the supplied key values. Done means identifying whether the failure is in algorithm handling or PEM input and documenting or fixing the reproducible cause.

Description

Trying to use ES256 by passing algorithm: 'ES256' into options and getting:

Error: error:0908F066:PEM routines:get_header_and_data:bad end line
    at Sign.sign (node:internal/crypto/sig:131:29)
    at sign (/Users/liamdoyle/Developer/limegorilla/apple-jwt-node-test/node_modules/jwa/index.js:152:45)
    at Object.sign (/Users/liamdoyle/Developer/limegorilla/apple-jwt-node-test/node_modules/jwa/index.js:200:27)
    at Object.jwsSign [as sign] (/Users/liamdoyle/Developer/limegorilla/apple-jwt-node-test/node_modules/jws/lib/sign-stream.js:32:24)
    at Object.module.exports [as sign] (/Users/liamdoyle/Developer/limegorilla/apple-jwt-node-test/node_modules/jsonwebtoken/sign.js:204:16)
    at file:///Users/liamdoyle/Developer/limegorilla/apple-jwt-node-test/app.js:22:26
    at ModuleJob.run (node:internal/modules/esm/module_job:185:25)
    at async Promise.all (index 0)
    at async ESMLoader.import (node:internal/modules/esm/loader:281:24)
    at async loadESM (node:internal/process/esm_loader:88:5) {
  library: 'PEM routines',
  function: 'get_header_and_data',
  reason: 'bad end line',
  code: 'ERR_OSSL_PEM_BAD_END_LINE'

Reproduction

let generatedToken = jwt.sign({
    iss: teamId, // Required by Apple
    exp: Math.floor(Date.now() / 1000) + (60 * 60),
}, token, {
    algorithm: 'ES256',
    header: {
        kid: keyId
    }
});

Also tried using this example from the readme:

jwt.sign({ foo: 'bar' }, privateKey, { algorithm: 'RS256' });

Same error.

Environment

Node 16.3
jsonwebtoken 8.5.1
macOS 12