Thanks, there was some misinformation on the topic of simultaneous call and browsing.
Also, what’s the proper way of checking IMS registration and Wifi Calling on any phone, not just Fairphone? My dad’s Realme C51 is on Simyo too, but it doesn’t react to the USSD code *#*#4636#*#*, which I thought was the only universally implemented code. Also, it has VoWifi enabled, but when I enable plane mode, connect it to wifi and try to make a call, it nevertheless asks me to leave plane mode or connect to wifi.