Thanks for the fix! My solution works now.

I'm pretty sure the 'Should work for random names' test is bugged:

TypeError: user.toLowerCase is not a function
    at /workspace/node/test.js:312:34
    at Array.map (<anonymous>)
    at solution (test.js:311:30)
    at Context.<anonymous> (test.js:305:52)
    at process.processImmediate (node:internal/timers:471:21)

I've checked many times whether I was causing the error, but everything seemed fine on my part. It's preventing me from passing all the tests.