how to update an array in laravel - laravel

Question

i have an array of data in a form that i want to update.when i update only the last column updated while the inputs that i updated do change.for example, we have a column size, price, and stock. the size include small,medium, and large and their respective prices and stock number. when i update the price of small size,it doesnt update but rather it updates the medium size.same for the large size also.i havent understood why only a specfic column is updating yet i have added a foreach to loop all the columns when updating.here is my update function.
public function editattributes(Request $request,$id)
{
$merchadisedata=Merchadise::select('id','merch_name','merch_code','merch_image')->find($id);
if ($request->isMethod('post')){
$data=$request->all();
foreach($data['attrid'] as $key=>$attr){
if(!empty($attr)){
Productattribute::where(['id'=>$data['attrid'][$key]])
->update([
'productattr_price'=>$data['productattr_price'][$key],
'productattr_stock'=>$data['productattr_stock'][$key],
]);
}
$message='Product attributes have been updated successfully';
Session::flash('success_message',$message);
return redirect()->back();
}
}
return view('backend.merchadise.editproductattributes')->with(compact('merchadisedata'));
}
on dd($data);die(); i get the inputs i have filled
here is the form in the blade file that am submitting
<form method="post" action="{{ url('admin/edit-attributes/'.$merchadisedata->id) }}">
{{csrf_field()}}
<table id="products" class="table table-striped table-bordered nowrap" style="width:100%;">
<thead>
<tr>
<th>Attribute Size</th>
<th>Attribute Stock</th>
<th>Attribute Price</th>
<th>Attribute Sku</th>
</tr>
</thead>
<tbody>
#foreach ( $merchadisedata->merchadiseattributes as $attribute)
<input type="text" name="attrid[]" value="{{ $attribute->id }}" style="display: none"/>
<tr>
<td>{{ $attribute->productattr_size}}</td>
<td>
<input type="number" name="productattr_stock[]" value="{{ $attribute->productattr_stock }}" required=""/>
</td>
<td>
<input type="number" name="productattr_price[]" value="{{ $attribute->productattr_price }}" required=""/>
</td>
<td>{{ $attribute->productattr_sku }}</td>
</tr>
#endforeach
</tbody>
</table>
<div class="form-group">
<button type="submit" class="btn btn-primary btn-sm btn-block">Submit</button>
</div>
</form>
where might i be going wrong in my code