1. In the client area, open the licence and check its status is Active and the licensed IP is the server's IP.
2. In the plugin, go to Settings → Licence and press Check now.
3. If it still shows Free, look at Last check-in in the client area. If it's empty or shows another address, the server connects out from a different IP (common behind NAT or a load balancer). Open a ticket with the server's outgoing IP and we'll add it.
4. Make sure outbound HTTPS to iam4hosts.com is allowed.