T-Mobile has suffered a major data breach, impacting some 200,000 customers.

Wireless carriers are prime cybersecurity targets, thanks to the wealth of customer data they have access to. According to T-Mobile’s disclosure, its cybersecurity team discovered unauthorized, malicious access to some of that customer information.

Fortunately, “the data accessed did not include names on the account, physical or email addresses, financial data, credit card information, social security numbers, tax ID, passwords, or PINs.” The hackers may have accessed “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.”

The company is working with law enforcement agencies and has begun notifying those customers affected.

This is the third major breach T-Mobile has suffered, and the second of 2020. Especially with T-Mobile’s newfound status as the second-largest carrier, it will need to do more to keep its customers’ data safe.