Routing issues when deploying to heroku?

Question

Node.js

I have a server that I want to upload to heroku.
The problem is that it does not want to work, and as I found out by typing, because I connect a common router:

const router = require('./routes/index')

app.use('/api', router)

And accordingly I get such an error


Well, if I remove this line, then everything will work and the usual app.get ('/') will be processed

How can I fix this?