French authorities are increasingly concerned about a rising issue in which mobile users experience sudden and unexplained loss of network connectivity. This phenomenon is often linked to a type of fraud known as SIM swapping, where cybercriminals transfer a victim’s phone number to a SIM card they control. Once the number is moved, fraudsters can intercept SMS messages, including two-factor authentication (2FA) codes used to secure online accounts and banking transactions. This allows them to access victims' accounts and steal funds quickly. In some cases, the financial losses can be substantial. In August 2026, one victim lost 17,000 euros in a matter of minutes, while another case involved nearly 600,000 euros stolen from around sixty people. According to the gendarmerie in the Somme region, an account can be completely drained in as little as 60 seconds once the SIM card is switched. The fraud typically starts with a phone call to the victim’s mobile operator, where scammers use personal information—such as a name, birthdate, or email—to request a new SIM card. Once the legitimate SIM is blocked, the fraudster receives all incoming SMS, including verification codes that grant access to online services. To reduce the risk of falling victim to this type of fraud, authorities recommend moving away from SMS-based authentication. Instead, they suggest using more secure methods such as authentication apps like Google Authenticator or Microsoft Authenticator, which generate codes directly on the user's device. These are harder for fraudsters to intercept. Newer security standards, such as FIDO2, are also gaining traction as reliable alternatives. If a user experiences a prolonged loss of network connectivity, especially if it’s accompanied by unusual email alerts, they should act quickly by contacting their mobile provider and bank to potentially limit damage. This issue is not confined to France. An international report from 2026 noted a 327% increase in SIM swapping fraud in Kenya, with over 123,000 fake SIM cards issued in a single year. The method remains largely the same worldwide, relying on the brief window of network disruption to act swiftly and avoid detection. As the threat continues to evolve, experts emphasize the importance of vigilance, prompt action, and legal accountability for service providers and financial institutions that may fail to protect their customers adequately.