livewire update not working even with key

Hi

i have 2 components parent and child. When i update something, the lists not refreshed. I assume it's the 'key' behaviour

in parent:

@foreach ($users as $user)
        <livewire:user.show :user="$user" :key="$user->id">
@endforeach

Assume, user table have two columns: username and email

when i update something from the child, it calls refresh button on my parent component

protected $listeners = [
        'userUpdated' => '$refresh'
    ];

    public function render()
    {
        $this->users = User::orderBy('id', 'desc')->get();

        return view('livewire.user.index');
    }

Problem: the lists not changing when i update it, i need to refresh first, then see the changes.

I tried adding 'username' as more unique key

        <livewire:user.show :user="$user" :key="$user->id. $user->username">

it did changes, when i update the username. but when i update the email, its not updating the list. Other fact: if i change the key to uniqid it also works, but not sure if it is a best practice

Not sure, what should i give the key in livewire to make it automatically adapat with any changes.