According to the statement, the company has recently found problems related to settings choices, which "may not have worked as intended."
"If you clicked or viewed an advertisement for a mobile application and subsequently interacted with the mobile application since May 2018, we may have shared certain data (e.g., country code, if you engaged with the ad and when, information about the ad, etc) with trusted measurement and advertising partners, even if you didn't give us permission to do so," the company said.
The statement added that the company could have shown users "ads based on inferences we made about the devices you use, even if you did not give us permission to do so."
The problems were fixed on August 5, but the investigation is still underway in order to find out how many people may have been impacted, the company assured.
All relevant information will be shared with users, according to Twitter.