After less than two years on the job, Marianne Radley, Pizza Hut’s U.S. chief brand officer, has resigned, and the company has given no reason for the departure.

The chain’s parent company, Yum Brands, issued a terse statement about the change in leadership: “Marianne Radley is no longer with Pizza Hut U. S. We appreciate her contribution to the brand and wish her well.” The company added that her replacement “will be the subject of a future announcement. ”

Prior to taking over as Pizza Hut’s brand chief in February 2018, Radley had served as senior vice president of global marketing at beverage company Monster Energy.

Radley’s abrupt departure is the second major change at Pizza Hut’s upper levels this year. Zipporah Allen, who had previously served as chief brand officer before moving into the role of chief marketing officer, quit to become vice president of brand marketing for Taco Bell, another Yum Brands asset.

According to The Drum, Radley “led a drive to bring back [Pizza Hut’s] original geometric ‘roof’ logo and a ‘confident and unapologetic tone of voice.’” She also led Pizza Hut’s move to replace Papa John’s as the NFL’s official pizza chain. She was recognized as one of the Top 100 Brand Innovators in the World for 2019.

But Pizza Hut has continued to struggle, closing hundreds of locations and reporting a 3 percent decline in same-store sells in Yum’s latest quarter.