If your server list is empty, the fix depends on which client you use.
Official VilaNet app
The app fetches your server list automatically after you sign in — there is nothing to import. If the list is empty, sign out and sign back in, and confirm the service on your account is active.
Third-party client using a subscription URL
An empty list usually means the subscription was pulled while it was inactive. See All nodes suddenly stopped working for the correct order of steps.
Older versions of this article suggested reconnecting to a "node list" server to restore the list. That mechanism is no longer in use and the advice no longer applies.