Connect your phone to WiFi and then go ahead on reset the network settings as described here https://drfone.wondershare.com/reset-iphone/reset-network-settings-iphone.html
Once this has complete you will need to reconnect your device with WiFi and hopefully this will resolve the issue.
Updates on iPhones can be either Software or Configuration, I think your phone was trying to do a configuration update, if it is an iPhone 12 this might likely be due to the 5G switch on with Virgin Media.