Value always null

[isaacdarcilla]

I have a Laravel Livewire input

<div class="col-sm-9">
      <input wire:model="school_official_telephone_number" value="{{ $school_official_telephone_number }}" class="form-control tagin" type="text" data-placeholder="Add...">
      @error('school_official_telephone_number') <span class="text-danger f-12 mt-1">{{ $message }}</span> @enderror
</div>

But when I click submit, the value was not recognized.

dd($this->school_official_telephone_number);

//results to `null`

Any help is much appreciated.