crach on calling api.getChatMember()

[1337G66k]

/Users/g66k/Code/JavaScript/node_modules/bluebird/js/release/async.js:49
fn = function () { throw arg; };
^
StatusCodeError: 400 - {"ok":false,"error_code":400,"description":"Bad Request: wrong user_id specified"}
at new StatusCodeError (/Users/g66k/Code/JavaScript/node_modules/request-promise-core/lib/errors.js:32:15)
at Request.plumbing.callback (/Users/g66k/Code/JavaScript/node_modules/request-promise-core/lib/plumbing.js:104:33)
at Request.RP$callback [as _callback] (/Users/g66k/Code/JavaScript/node_modules/request-promise-core/lib/plumbing.js:46:31)
at Request.self.callback (/Users/g66k/Code/JavaScript/node_modules/request/request.js:185:22)
at Request.emit (events.js:310:20)
at Request. (/Users/g66k/Code/JavaScript/node_modules/request/request.js:1161:10)
at Request.emit (events.js:310:20)
at IncomingMessage. (/Users/g66k/Code/JavaScript/node_modules/request/request.js:1083:12)
at Object.onceWrapper (events.js:416:28)
at IncomingMessage.emit (events.js:322:22)
at endReadableNT (_stream_readable.js:1187:12)
at processTicksAndRejections (internal/process/task_queues.js:84:21) {

[mast]

Please check your user_id field. It have to be Integer identity of user. You get it in update at path update.message.from.id.