Some networks don't show the VoLTE option and enable it by default but don't allow you to turn it off example I have an EE SIM and a Vodafone SIM and only EE allow me to toggle it on and off but VoLTE still works on the Vodafone SIM when you make a call does it stay on 4G or does it drop down to 3G/2G?
Same issue on my A52 5g. Volte toggle was there before the latest update, now it's missing. Major headache for me as I had to switch this off to stop phone calls on my car coming up as unknown even though it has my contacts list. As I can't turn this feature off now, contacts are coming up as unknown again. I'm on Vodafone and the option was there. It's down to Samsung. Unbelievable