How to fix issue in LiveWire and Laravel saying: "Cannot read property 'fingerprint' of null" ?

Actually it is really simple.

Most likely you have been using nested livewire components and in this case be sure to use unique livewire key for each component.

So, for example let's say we are including livewire component in a blade loop :

                    @foreach($data as $index => $key)

  @livewire('search',['param1'=>'param1value'],key($fightCardSection.$index.'fighter1'))

@endforeach
                  

in this case you will probably face the issue "Cannot read property 'fingerprint' of null" or something similar and it is happening because livewire needs to have unique :key on every nested component.

                    @foreach($data as $index => $key)

  @livewire('search',['param1'=>'param1value'],key($index))

@endforeach
                  

in some cases (especially if you have nested loops you will have to make this key more unique. Easiest is by including time param:

                    @foreach($data as $index => $key)

  @livewire('search',['param1'=>'param1value'],key($index.time()))

@endforeach