Why I receive Error 403 from API?

Good morning. I am a beginner of p.s.m. Firts I tried the following from the browser, and it worked and it still works: https://nominatim.openstreetmap.org/search?street=via+tolmezzo+15&postcode=20132&city=milano&county=MI&country_code=IT&format=json

Then I tried with php, with the following instructions, both from my pc that from a server, but it always return an Error 403. I read that this happens when there is an abuse, but it happened me from the very first submissmion. Thank you.

$data = array( 'street' => "via tolmezzo 15", 'postcode' => "20132", 'city' => "Milano", 'county' => "MI",
'country_code' => "IT", 'format' => "json" ); $options = array ( 'http' => array ( 'header' => "Content-type: application/x-www-form-urlencoded\r\n", 'method' => 'GET', 'content' => http_build_query($data) ) ); $url="https://nominatim.openstreetmap.org/search"; $context = stream_context_create ($options); $result = file_get_contents ($url, false, $context);