Store multiple data with file upload and insert in multiple rows in database - file-upload

Question

I want to store some data in multiple rows in database. I can store this data without any file. But I cannot store data with file. How can I store data with upload file and also empty file field. Please help. It will be more helpful for me.
My contoller is look like this:
public function store(Request $request) {
$id = '12';
foreach($request->pass_issue_con as $key=>$v) {
$data = [
'emp_id'=>$id,
'pass_issue_con'=>$v,
'pass_no'=>$request->pass_no[$key],
'pass_issue'=>$request->pass_issue[$key],
'pass_expiry'=>$request->pass_expiry[$key],
'pass_biometric'=>$request->pass_biometric[$key],
'pass_doc'=>$request->pass_doc[$key]
];
EmployeeTravelDocumentsInfo::insert($data);
}
return redirect()->back()->with('message', 'Data Has Been Submitted Successfully!');
}
My Blade file is look like this:
<form action="{{ route('registration.store') }}" method="post" enctype="multipart/form-data">
#csrf
<td>
<select class="form-control select2" style="width: 100%;" name="pass_issue_con[]">
<option value="N/A">Choose an item...</option>
#foreach( $countries as $country)
<option value="{{$country->id}}">{{$country->nicename}}</option>
#endforeach
</select>
</td>
<td><input type="text" name="pass_no[]" class="form-control" style="width:160px;"></td>
<td><input type="date" name="pass_issue[]" class="form-control"></td>
<td><input type="date" name="pass_expiry[]" class="form-control"></td>
<td>
<select class="form-control select2" style="width: 100%;" name="pass_biometric[]">
<option>Choose an item...</option>
<option value="0">Yes</option>
<option value="1">No</option>
</select>
</td>
<td><input type="file" class="form-control" name="pass_doc[]" style="width:160px;" multiple></td>
</tr>
</tbody>
</table>
</div>
<div class="row">
<div class="col-md-12 mt-3 pb-3 pr-3 text-right"><input type="submit" name="" value="SAVE" class="btn btn-lg btn-success"></div>
</div>
</form>
$('.pass thead').on('click', '.passAdd', function(){
var pass = "<tr>"+
"<td><a href='javascript:void(0)' class='btn btn-sm btn-danger passDelete'>-</a></td>"+
"<td>"+
"<select class='form-control select2' style='width: 100%;' name='pass_issue_con[]'>"+
"<option>Choose an item...</option>"+
"#foreach( $countries as $country)"+
"<option value='{{$country->id}}'>{{$country->nicename}}</option>"+
"#endforeach"+
"</select>"+
"</td>"+
"<td class='column'><input type='text' name='pass_no[]' class='form-control'></td>"+
"<td class='column'><input type='date' name='pass_issue[]' class='form-control'></td>"+
"<td class='column'><input type='date' name='pass_expiry[]' class='form-control'></td>"+
"<td class='column'><select class='form-control' style='width: 100%;' name='pass_biometric[]'>"+
"<option>Choose an item...</option>"+
"<option value='0'>Yes</option>"+
"<option value='1'>No</option>"+
"</select>"+
"</td>"+
"<td><input type='file' class='form-control' name='pass_doc[]'></td>"+
"</tr>"
$('.pass tbody').append(pass);
$('.pass tbody').on('click', '.passDelete', function(){
$(this).parent().parent().remove();
});
});