Please confirm if the steps taken so far from you are the ones below:
-VPN Properties >>>>>>>>> Routing and Remote Access>>>>>>>>>Allow custom IPSec policy for L2TP/IKEv2 connection
-IPv4 tab >>>>>>>>> Enable IPv4 forwarding >>>>>>>>>Static address pool
-NAT tab >>>>>>>>> New interface >>>>>>>>> Public interface connected to Internet >>>>>>>>>Enable NAT on this interface
-Port tab >>>>>>>>> VPN Server(L2TP/IPSec on this server)
-Change IP address to 127.0.0.1
-Restart required
-Firewall settings configuration >>>>>> Inbound/outbound rules (allow Routing and remote access) >> Allow the connection
-VPN user profile set up (Allow the user connection)
-Recall to share the PSK(Preshared KEY with all users)
Looking forward to your feedback,
Cheers,
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