Cannot serve build directory: Uncaught SyntaxError: Unexpected token '<

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8 

module.exports = ({ env }) => ({
  host: env('HOST', '0.0.0.0'),
  port: env.int('PORT', 1337),
  url: 'https://api.example.com',
  app: {
    keys: env.array('APP_KEYS'),
  },
});

Update your ./config/server.js with the appropriate url aka https if you have ssl cert setup; if not, then use http.

Also, triple check on cache problems with jwt tokens. Clean data for browsers.