The U.K.’s data protection authority fined the country’s largest mobile network operator 100,000 pounds ($127,205) for sending over 2.5 million unwanted advertisements over text.

The Information Commissioner’s Office found that EE Limited violated the Data Protection Act (DPA), which protects consumers against unsolicited marketing, according to a statement. The company must pay the fine by July 23.

“We accept the ICO’s findings, and we’re working to improve our internal processes. We’re committed to ensuring our customers are fully aware...