In a data breach that occurred in November, 37 million active users' personal information was acquired by a "bad actor," according to T-Mobile.
The hacker took customer information including names, billing addresses, emails, phone numbers, dates of birth, T-Mobile account numbers, and details on the cellular carrier's services they use.
According to T-Mobile, the theft did not reveal any financial information, social security numbers, credit card details, government ID numbers, passwords, or PINs.
However, con artists can combine that data with other stolen or widely available data and use it to steal people's identities or money.
In addition to engaging with law authorities, T-Mobile said it has started notifying consumers whose information may have been compromised.
T-Mobile stated in a statement that "protecting our customers' data remains a top concern."
"We will keep making significant expenditures to improve our cybersecurity programme"