我正在尝试在heroku dyno上转发端口，并得到以下错误消息：
amirb$ heroku ps:forward 9090
Establishing credentials... error
▸ Could not connect to dyno!
▸ Check if the dyno is running with `heroku ps'
amirb$ heroku ps
=== worker (Hobby): npm run start:debug (1)
worker.1: up 2018/07/11 10:31:12 -0700 (~ 2m ago)
有什么主意吗？