Singtel and DBS outages indicate that service providers should review the resilience of their systems, says cybersecurity expert Matthias Yeo. SINGAPORE: When Singtel mobile service disruptions hit between Mar 16 and Mar 18 , many customers in Singapore were unable to make phone calls or e-payments.  Preliminary reports suggest 600,000 Singtel customers were affected by the Mar 16 outage, which lasted nine hours, while 2,000 customers faced mobile connectivity issues the next day. The Infocomm