Hello,
Most VPN configurations in Teltonika devices accept domain names, meaning that you can establish tunnel with dynamic IP in combination with DDNS service. The issue here is that after the initial tunnel configuration, the domain name is not resolved later, which results in need to restart network configuration.
Development department is aware of this and update is planned, but not in the near future.
You can also check a suggestion from another thread for wireguard interface here.
On the other hand, you can try ZeroTier VPN service, which does not require public IP.
Best regards,
