diff --git a/app/Filament/Resources/InvoiceValidationResource.php b/app/Filament/Resources/InvoiceValidationResource.php
index 589a9fe..fb02a38 100644
--- a/app/Filament/Resources/InvoiceValidationResource.php
+++ b/app/Filament/Resources/InvoiceValidationResource.php
@@ -385,6 +385,11 @@ class InvoiceValidationResource extends Resource
                             ->afterStateUpdated(function ($state, callable $set, callable $get) {
                                 $set('invoice_serial_number', null);
                                 $plantId = $get('plant_id');
+                                if (! $plantId) {
+                                    $set('invoice_serial_number', null);
+
+                                    return;
+                                }
                                 $plantCode = Plant::find($plantId)?->code ?? null;
 
                                 $directory = "uploads/temp/{$plantCode}";
@@ -399,7 +404,7 @@ class InvoiceValidationResource extends Resource
                             ->required()
                             ->acceptedFileTypes([
                                 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet',
-                                'application/vnd.ms-excel', // Legacy .xls fallback if needed
+                                // 'application/vnd.ms-excel', // Legacy .xls fallback if needed
                             ])
                             ->rules(['mimes:xlsx']) // Laravel validation: extension check
                             ->preserveFilenames() // <- this keeps the original filename
@@ -729,6 +734,11 @@ class InvoiceValidationResource extends Resource
                             ->afterStateUpdated(function ($state, callable $set, callable $get) {
                                 $set('invoice_material', null);
                                 $plantId = $get('plant_id');
+                                if (! $plantId) {
+                                    $set('invoice_material', null);
+
+                                    return;
+                                }
                                 $plantCode = Plant::find($plantId)?->code ?? null;
 
                                 $directory = "uploads/temp/{$plantCode}";
@@ -741,10 +751,15 @@ class InvoiceValidationResource extends Resource
                         FileUpload::make('invoice_material')
                             ->label('Invoice Material')
                             ->required()
+                            ->acceptedFileTypes([
+                                'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet',
+                                // 'application/vnd.ms-excel', // Legacy .xls fallback if needed
+                            ])
+                            ->rules(['mimes:xlsx']) // Laravel validation: extension check
                             ->preserveFilenames() // <- this keeps the original filename
                             ->reactive()
-                            ->storeFiles(false) // prevent auto-storing
-                            ->disk('local')
+                            ->storeFiles(false) // prevent auto-storing, we will store manually
+                            ->disk('local') // 'local' refers to the local storage disk defined in config/filesystems.php, typically pointing to storage/app.
                             ->visible(fn (Get $get) => ! empty($get('plant_id')))
                             ->directory(function (callable $get) {
                                 $plant = Plant::find($get('plant_id'));
@@ -752,6 +767,7 @@ class InvoiceValidationResource extends Resource
 
                                 return "uploads/temp/{$plantCode}";
                             })
+                            ->uploadingMessage('Uploading...')
                             ->helperText('Only .xlsx files are allowed (Excel files).'),
                     ])
                     ->action(function (array $data) {