T-Mobile will pay $31.5 million in a data protection and cybersecurity settlement with the Federal Communications Commission, resolving investigations into data breaches that impacted millions of U.S. consumers, the agency announced Monday.

According to an FCC news release, T-Mobile has agreed to address “foundational security flaws, work to improve cyber hygiene, and adopt robust modern architectures, like zero trust and phishing-resistant multi-factor authentication.”

The Bellevue, Wash.-based wireless carrier will invest $15.75 million in cybersecurity, in what the FCC calls “a model for the mobile telecommunications industry.” The settlement also includes a $15.75 million civil penalty which T-Mobile must pay to the U.S. Treasury.