Ensure to copy your n8n workflow and paste it in the code block, that is in between the pairs of triple backticks, which also could be achieved by clicking </> (preformatted text) in the editor and pasting in your workflow.
```
<your workflow>
```
That implies to any JSON output you would like to share with us.
Make sure that you have removed any sensitive information from your workflow and include dummy or pinned data with it!
That would be a problem for any connection. VPN implies establishing a secure tunnel between client and the server. In other words, you have to create that tunnel on n8n instance. Unless you self-host, that is not possible on n8n Cloud.