ODK Collect forms on smartphone

Hell all,

I am working on project perception survey on the public bike-sharing system. I am facing difficulty with below error.

I am able to connect to the ODK Aggregate server from my phone over our wifi network, both through the web interface and ODK Connect. It allows me to view blank forms, but when I select a form and hit "get selected" I get an error:

failed to connect to (port 443) = after30000ms: isConnected failed; ECONNREFUSED (Connection refused)

Could you please anyone guide me on how to resolve this.

ODK Aggregate is running on the latest version of the VM and ODK Collect is the latest android app version.