Direct answer
IPv6 can cause connection symptoms when rules, DNS or the selected node only handle IPv4 cleanly. Temporarily disable IPv6 or add explicit IPv6 rules to confirm whether it is the cause.
What to check first
Treat connection symptoms as a layered support check: profile update, node availability, rule match, DNS result, local proxy port, system permission and target website behavior all need to be isolated.
- Test with one known-good node and one simple website first.
- Compare Rule mode and Global mode to separate routing from node availability.
- Check DNS logs, local proxy ports and system proxy settings.
- Record status messages and timestamps before contacting provider support.
Recommended handling
Keep the troubleshooting path narrow: confirm the profile, confirm the selected node, test Rule mode, read the log, then change only the setting that matches the observed status message.
Practical notes
- Change one setting at a time so the result is attributable.
- Use logs and timestamps when asking for provider or community support.