Laravel function ignores return

in my laravel application I have a function that is ignoring a return, and it returns the RedirectResponse.
Hear my code.
This is the call:

public function updateReservationAPI(Booking $booking)
{
    try {
        $idReturned = $this->getReservationByDate($booking->arrival);
    } catch (Exception $e) {
        dd("Error on API call: " . $e->getMessage());
    }
}

And this is the code of the function:

private function getReservationByDate($date, $page = 1)
{
    $dateParam = Carbon::parse($date);
    $url = "https://api.site.url/api/reservations";
    $nextPage = "";

    if (Session::has('access_token')) {
        $client = new Client();
        $response = $client->get($url, [
            'headers' => [
                'Authorization' => 'JWT ' . Session::get('access_token'),
            ],
            'query' => [
                'page' => $page,
            ],
        ]);

        $statusCode = $response->getStatusCode();
        if ($statusCode === 200) {
            $body = $response->getBody()->getContents();
            $data = json_decode($body, true);

            $nextLink = $data["next"];
            if (!is_null($nextLink)) {
                $parsedUrl = parse_url($nextLink);
                parse_str($parsedUrl['query'], $queryParams);
                $nextPage = $queryParams['page'];
            }
            $results = $data['results'];

            $idToReturn = null;
            foreach ($results as $result) {
                $dataItem = Carbon::parse($result["register_date"]);

                if ($dateParam->isSameDay($dataItem)) {
                    $idToReturn = $result["id"];
                    return $idToReturn;
                }

            }
            if (!is_null($nextLink)) {
                return $this->getReservationByDate($date, $nextPage);
            }
        }

    } else {
        $this->loginAPI();
        $this->getReservationByDateAPI($date, $page);
    }
    return redirect()->back();
}

I would to return the id found on if ($dateParam->isSameDay($dataItem)) statement but I get an IlluminateHttpRedirectResponse response.

If I try to put dd($idToReturn) just before the return, I get the expected data.