setAccessKey("your ak"); $client->setSecretKey("your sk"); $body = [ 'Caller' => "137XXXX8257", 'Callee' => "158XXXX9130", 'CallerNumberPoolNo' => 'NP163517154204092175', 'CalleeNumberPoolNo' => 'NP163517154204092175', ]; $response = $client->Click2Call($body); echo $response;