Configure clients on laptop/mobile using private/public ip

Did you checked if Port Forwarding is still enabled?

Did you checked that FQDN is still bounded to your IP? Check if it returns your external IP address, it could be changed with time

dig yourFQDN

Sorry, not familiar with your Router.

Could you please trace it?

  1. Try to connect to the FQDN with curl
    curl -v -k https://FQDN
    Check in output of it, is it able to connect? What IP Address is there?
  2. Try to connect directly to your Internal IP to the NC and check if it works:
    curl -v -k https://IP
  3. Try to connect directly to your External IP (that you see in a dig command) to the NC and check if it works:
    curl -v -k https://externalIP
  4. Check in WebServer Logs. Are you hitting WebServer at all and if an error comes.