American mobile operator T-Mobile has suffered a security breach that may have exposed call records and phone numbers for some of its customers.

T-Mobile said the data breach did not expose customers’ names, physical addresses, email addresses, financial data, credit card information, social security numbers, tax IDs, passwords or PINs.

T-Mobile, which is owned by Deutsche Telekom of Germany, said the breach exposed customers’ proprietary network information (CPNI), including phone numbers and call records.

T-Mobile in a security update said customer proprietary network information (CPNI) as defined by the Federal Communications Commission (FCC) rules was accessed.

The CPNI accessed may have included phone number, number of lines subscribed to on your account and, in some cases, call-related information collected as part of the normal operation of your wireless service.

Earlier breaches at T-Mobile exposed customers’ information in 2018, prepaid customers’ information in 2019 and exposed customer and financial data in March last year.

T-Mobile said the fresh breach affected less than 0.2 percent of its customers. T-Mobile competes with AT&T and Verizon Wireless.

T-Mobile has approximately 100 million customers, which equates to around 200,000 people affected by this breach.

The fastest growing telecom service provider was alerting affected customers that a security incident exposed their account’s information.