T-Mobile says it is investigating a leak of its data after someone took to an online forum offering to sell the personal information of cellphone users.

The company said Monday that it has confirmed there was unauthorized access to “some T-Mobile data” but was still determining the scope of the breach and who was affected.

It also said it was confident that it has closed the entry point used to gain access. Vice’s Motherboard reported Sunday that someone was offering to sell personal data from more than 100 million people.

T-Mobile hasn't said how many were affected.

LOOK: The Most Famous Actor Born Every Year

LOOK: The most famous actress born the same year as you

Many of the actresses in this story not only made a name for themselves through their collection of iconic performances, but also through the selfless, philanthropic nature with which many of them approached their stardom. In an age of flipping the script on societal norms, many of these actresses are using their voices and platforms to be advocates for those who are otherwise unheard.