This is still unconfirmed IMO since all news stories seem to point to the Vice news article. YMMV
https://nypost.com/2021/08/16/t-mobile-probes-data-breach-affecting-nearly-all-us-customers-report/
QuoteVice said the data breach includes social security numbers, phone numbers, names, physical addresses, drivers license information and unique 15-digit numbers identifying customers mobile phones, also known as IMEI numbers.
"We are aware of claims made in an underground forum and have been actively investigating their validity. We do not have any additional information to share at this time," a T-Mobile spokeswoman told The Post on Monday.
Vice said the forum doesn't mention T-Mobile, but that the hacker who posted the information told the news outlet that they have obtained the data of over 100 million customers from T-Mobile servers.
One guess as to which cellular provider I switched to LAST WEEK... Grrr...
Multiple sites and Mobile have confirmed the data loss - everything - name SSN Drivers license address - the entire fish.