Did you register the ASA with a Smart license token yet? You will need to do so and make sure that the "allow export controlled features" tick box is checked in your smart portal when creating the registration token. That will ensure that 3DES-AES licensing is enabled which allows the ASA to activate modern cryptographic protocol support.
We hadn't registered the smart license token yet. We would like to understand whether due to this we are not able to access it from Outside Network. As the Firewalls installed in Air-Gapped(On-Perm). During Purchase of the Firewall we have to request for PLR ?