No 'Access-Control-Allow-Origin'

Estou tentando consumir os dados vindos pela API mas está dando erro: from origin 'null' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource.

 function RequestService() {
 $.ajax({
 type: "GET",
 url: "https://api.sympla.com.br/public/v3/events",
 contentType: "application/json; charset=utf-8",
 headers: "Access-Control-Allow-Origin: https://meusite.com",
 data: "{}",
 dataType: "json",
 success: function(data) { SucessCallback(data.d); },
 error: function(data) { FailureCallBack(data); }
 });
 }