Hello,
If you are certain that the TCP port is open on any software firewalls onyour VPS, you should also check:
– If you have set the rpcbind config set correctly.
– Check with your hosting provider, they are likely running their own firewalls. They can add an exception for you.
Since you mentioned that you are on a VPS, know that during the IBD (Initial Blockchain Download), the wallet may use more resources (CPU, net) than you are allowed to use on a sliced host. In that case, your host may be auto-banned. Many hosts do this, depending on what rules they have. You may need to talk to them about this as well.
with regards,
Alex