Please don't bothered about this it's server's error of Airtel. If you like please accept as a solution it's help to others users also, click on 3dots in my reply section and click on accept solution. Thanks.
As per the information, your device is compatible with 5g service and you can also check it from your device as well using some steps.
Settings> Connections> Mobile networks> network mode SIM1 or SIM2> network mode> Check device network mode as 5G/LTE/3G/2G (auto connect) mode.
Although, as per the source I have checked that this device comes with 5g support from the company side, however, you can use a 5g network on it. If you have other concerns regarding Samsung products kindly feel free to get in touch with us.
