Illuminate\Validation\ValidationException: The customer id field is required

@tykus ErrorException: Attempt to read property "1" on null in C:\xampp\htdocs\optical\app\Http\Controllers\FinanceController.php:83

 public function update(Request $request, Finance $finances, $id)
    {
        try {

            $this->validate($request, [
                'personal_id' => 'required|exists:customers,personal_id',
                'test_id' => 'required|exists:p_tests,id',
                'amount' => 'required|integer',
                'date' => 'required'
            ]);
            $test = PersonalTest::findOrFail($request->id);
            $finance = Customer::findOrFail($request->id);
            $finances->update([
                'customer_id' => $finance->customer->$id,
                'test_id' => $test->id,
                'date' => $request->date,
                'amount' => $request->amount,
                'note' => $request->note
            ]);
            return redirect()->back()->with('success', 'تم تحديث معلومات مالية جديدة');
        } catch (Exception $ex) {
        // dd($request);
            return $ex;
            return redirect()->back()->with('message', 'حدث خطأ ما');
        }
    }

@tykus customer_id refers to personal_id

@moh120 this

'customer_id' => $finance->customer->$id,

should be

'customer_id' => $finance->customer->id,

customer_id refers to personal_id

Try to use appropriate and consistent property names.

@tykus still not working

@tykus what should i ise in the blade

 <form class="form" action="{{ route('admin.finance.update',['id'=>$finance->id]) }}" method="POST"
                                            enctype="multipart/form-data">
                                            @csrf
                                            @method('PUT')
                                            <div class="form-body">
                                                <h4 class="form-section"><i class="ft-home"></i>  finance details </h4>
                                                <div class="row">
                                                    <div class="col-md-6">
                                                        <div class="form-group">
                                                            <label for="projectinput1"> national id  </label>
                                                            <input type="text" value="{{$finance->customer->personal_id}}" id="customer_id"
                                                                class="form-control"
                                                                name="customer_id">
                                                            @error('customer_id')
                                                                <span class="text-danger">{{ $message }}</span>
                                                            @enderror
                                                        </div>
                                                    </div>

@moh120 I don't know... your variable and property naming are inconsistent! Look here at the customer_id input; it's value is derived from the personal_id of a different model (to $finance) - why?

<input type="text" 
       value="{{$finance->customer->personal_id}}" 
       id="customer_id"
       class="form-control"
       name="customer_id">

@tykus the var name in finance model id customer_id refers to personal_id in another model

@moh120 so it should be like this:

<input type="text" 
       value="{{$finance->customer_id}}" 
       id="customer_id"
       class="form-control"
       name="customer_id">

And the Controller action like this; without unnecessary queries and try/catch (handle exceptions in the exceptions Handler.php class:

 public function update(Request $request, Finance $finances, $id)
{
    $this->validate($request, [
        'customer_id' => 'required|exists:customers,personal_id',
        'test_id' => 'required|exists:p_tests,id',
        'amount' => 'required|integer',
        'date' => 'required'
     ]);

    $finances->update([
        'customer_id' => $request->customer_id,
        'test_id' => $id,
        'date' => $request->date,
        'amount' => $request->amount,
        'note' => $request->note
    ]);
    return redirect()->back()->with('success', 'تم تحديث معلومات مالية جديدة');
}