From the BBC - What to do if your Phone is Stolen

[Oxonian]

This contains some useful guidance :-

BBC One - Rip Off Britain - What to do if your Phone is Stolen

https://www.bbc.co.uk/programmes/articles/4SRrKX6GQdcqsGGNz4tvmqk/what-to-do-if-your-phone-is-stolen