Recently my CP Server Certificate was about to expire, after wich I renew it with a new PositiveSSL certificate.
For some reason, this certificate is not automatically accepted on the guest network, when using security level "Internal - Acknowledged" or "Internal - Authenticated".
Only after manually accepting the certificate in the device (iPhone or MACOS) the devices are able to authenticate.
How should a certificate be prepared, to be able to properly work for a captive-portal?