getting error as \"status\":\"error\",\"message\":\"Token is invalid or has expired

Still i am getting this error

Unhandled rejection StatusCodeError: 403 - "{\"status\":\"error\",\"message\":\"Token is invalid or has expired.\",\"data\":null,\"error_type\":\"TokenExcepti
at new StatusCodeError (C:\vivekblocklyproject\node_modules\request-promise-core\lib\errors.js:32:15)
at C:\vivekblocklyproject\node_modules\request-promise-core\lib\plumbing.js:97:41
at tryCatcher (C:\vivekblocklyproject\node_modules\request-promise\node_modules\bluebird\js\release\util.js:16:23)
at Promise._settlePromiseFromHandler (C:\vivekblocklyproject\node_modules\request-promise\node_modules\bluebird\js\release\promise.js:512:31)
at Promise._settlePromise (C:\vivekblocklyproject\node_modules\request-promise\node_modules\bluebird\js\release\promise.js:569:18)
at Promise._settlePromiseCtx (C:\vivekblocklyproject\node_modules\request-promise\node_modules\bluebird\js\release\promise.js:606:10)
at Async._drainQueue (C:\vivekblocklyproject\node_modules\request-promise\n

my code is :-
var KiteTicker = require("./views/scripts/kiteconnect").KiteTicker;
var ticker = new KiteTicker("**************", access_token);

ticker.connect();
ticker.on("ticks", onTicks);
ticker.on("connect", subscribe);

function subscribe() {
var items = [instrument_token];
ticker.subscribe(items);
ticker.setMode(ticker.modeFull, items);
}

function onTicks(ticks) {
//if (redirectpage == 'http://localhost:8383/chart') {
list.add(ticks[0]);
console.log(ticks[0]);
StartAPI();
//console.log(list.length);
blocks.sort(sortAscending);
io.emit('ticks', { blocks: blocks });
io.emit('ticker', { data: ticks[0] });
}

kindly help me thanks in advance