How to Link Dokku App to Managed Database

I have a small problem here. I have an app setup on Dokku vps, works well with the Dokku Postgress plugin. But I want to switch things up and use the digitalOcean managed Database(Postgress) Since changing the database url to the managed database url: postgresql://password@host:port/db-name?sslmode=require I get this error when I rerun the container:

appname web container output: Error: connect ECONNREFUSED 127.0.0.1:5432 at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1146:16) { errno: -111, code: ‘ECONNREFUSED’, syscall: ‘connect’, address: ‘127.0.0.1’, port: 5432 }