External access not working after replacing modem

hey, I replaced my modem and now external access is not working… I getting an error related to the certificate.
Local access using the private IP (http) works fine. Also SSH externally is ok too. Port forwarding is done too om the modem.

any ideas how to troubleshoot this issue because I am lost?
what should the http part in the configuration.yaml should look like? please help I am lost :sob: