when user cancel

I have this code, everything works fine until users cancel during the UTL_HTTP.GET_RESPONSE than the connection stay in CLOSE_WAIT when the session reach to 5 of these connections I'm getting "too many open HTTP requests"

 resp := UTL_HTTP.GET_RESPONSE(req);
  DBMS_OUTPUT.PUT_LINE('HTTP response status code: ' || resp.status_code);
  DBMS_OUTPUT.PUT_LINE('HTTP response reason phrase: ' || resp.reason_phrase);
  FOR i IN 1..UTL_HTTP.GET_HEADER_COUNT(resp) LOOP
    UTL_HTTP.GET_HEADER(resp, i, name, value);
    DBMS_OUTPUT.PUT_LINE(name || ': ' || value);
  END LOOP;
  UTL_HTTP.END_RESPONSE(resp);

EXCEPTION
      WHEN OTHERS
      THEN
        IF v_utl_resp.private_hndl IS NOT NULL
         THEN
            UTL_HTTP.end_response (v_utl_resp);
         END IF;
        IF v_utl_req.private_hndl IS NOT NULL
        THEN
            UTL_HTTP.end_request(v_utl_req);
        END IF; 
      RAISE;
END;