Below are some steps to help diagnose and resolve this issue:

1. Check for the latest updates on your device.
2. Check if the VPN software is up to date.
3. Check your network connection. Is there bandwidth bottleneck or overload?
4. If any, power cycle your modem and router.
5. Check if your internet speed is up to the desired specifications.
6. Review network settings to ensure nothing is interfering with your VPN connection.
7. Check if the VPN software is configured correctly to connect to the network.
8. Remove any foreign IPs from your network.
9. Inspect the router settings, especially firewall and security settings and see if it is blocking the VPN.