Jack Monroe says she has lost about £5,000 after her phone number was hijacked and re-activated on another Sim card.
The criminals were then able to receive her two-factor authentication messages and access her bank and payment accounts.
The bestselling food writer tweeted she was “paranoid about security” and already had strong measures in place.
A privacy campaigner said the industry had failed to address “Simjacking”.
Ms Monroe tweeted she was “white-hot angry” and had been told although she should get her phone number back soon ... Read even more
