Ho to filter child table selected using with clause in laravel

I am querying Item using following:

$itemdata = Item::with('itemimagedetails')
    ->with('variation')
    ->select('item.id', 'item.cat_id', 'item.item_name', 'item.item_description', 'item.brand', 'item.manufacturer', 'item.country_origin', 'item.ingredient_type', 'item.delivery_time', 'categories.category_name', 'item.category_unit')
    ->join('categories','item.cat_id','=','categories.id')
    ->where('item.id', $request['item_id'])->get()->first();

I want to filter variations using planid fetched from user table.

$plan = User::where('id', $request['user_id'])

I have tried:

if (count($itemdata->variation) > 0) {
    $plan = User::where('id', $request['user_id'])->get();

    foreach ($itemdata->variation as $key => $tag_name) {
        if($tag_name == $plan['plan_id']) {
            unset($itemdata->variation[$key]);
        }
    }
}

But then I get an error in the API calls.

Can someone please suggest best approach?

source https://stackoverflow.com/questions/70315250/ho-to-filter-child-table-selected-using-with-clause-in-laravel