First identify the stage where the problem occurs: the subscription will not import, the server list is empty or the connection will not start. If the app shows a connection but websites do not open, record that too: client status does not replace checking access.
Change one setting at a time and test the result after each action. This helps you find a working option and explain to support what you have already checked.
Check in order
Internet without the VPN. Disconnect and open a familiar website. If you have no access, check the network itself. Public Wi-Fi may require signing in through a network page; do not enter subscription details there.
Subscription status. Check the expiry date and account details. Refresh the subscription in the client. If import fails, copy the entire link again without surrounding text.
Client status. Check whether a server is selected and the connection starts. Record the app’s exact message and the error time.
Conflicting connections. Make sure another VPN client is not running at the same time. Restart your chosen app and reconnect.
Understanding the result
It also fails without the VPN. Restore internet access first. Switching servers will not fix a missing connection to the network itself.
The connection will not start. Save the selected server’s name and the client message. One failed attempt does not yet explain the cause.
One website will not open. Try several other addresses. If they work, save the error message and contact that website’s support.
Prepare a clear message
Include the system, client version, network, location, test time and error text. For example: ‘The connection will not start on my laptop over home Wi-Fi; internet works without the VPN; subscription refreshed; client message: [error text].’
Do not reset all settings before saving this information. If sharing a log, review its contents and hide keys, the subscription address and other access details.