Pagination not working

I am trying to fetch few records from DB and applying pagination on results but pagination seems not to be working. Here is my code snippet:

Class City {
public function ads() {
        return $this->hasManyThrough('Sello\Ad', 'Sello\User');
    }
}


public function getAdsFeedWithFilters(Request $request) {

// fetch request params

$ads = $city->load(['ads' => function($query) use (
            $termsRS,
            $checkForSearchTerm,
            $checkForPostedWithin, $checkForPriceRange,
            $sortByColumn, $sortOrder, $postedWithin, $priceEndRange, $priceStartRange) {

            $query->where('status', '=', Ad::$STATUS_DRAFT);

            if ($checkForPriceRange) {
                $query->where('price', '>=', $priceStartRange);
                $query->where('price', '<=', $priceEndRange);
            }

            if ($checkForPostedWithin) {
                $query->whereRaw('creation_date >= NOW() - INTERVAL ' . $postedWithin . ' DAY');
            }

            if ($checkForSearchTerm) {
                $query->whereRaw("MATCH (title) AGAINST (?)", [$termsRS]);
            }

            $query->orderBy($sortByColumn, $sortOrder);

            $query->paginate(Ad::$ADS_PER_PAGE);

        }]);

// return results
return ResponseFormatter::format($code, $message, $ads);

}

I get the required results but result object does not contains fields like pageNo, totalPages, Next and Previous page urls etc.