Cannot add property auth_pass, object is not extensible

[Wu Zhuokun]

I meet this problem:'Error while starting up server TypeError: Cannot add property auth_pass, object is not extensible'.
And I use kod-redis like this:

import redisStore from 'koa-redis';

app.use(session({
prefix: "prefix",
ttl: 40000,
rolling: true,
store: redisStore({
"host": "192.168.199.189",
"port": 6379,
"db": 2
})
}));

[Tümay Çeber]

Why this ticket closed without explanation? I am getting similar error
TypeError: Cannot add property password, object is not extensible at new RedisStore (/app/node_modules/koa-redis/lib/index.js:54:20) at RedisStore