Amazon-owned Whole Foods is asking the National Labor Relations Board to set aside the results of a union election that led to a labor win.

Last month, workers at a Whole Foods store in Philadelphia voted in favor of joining the United Food and Commercial Workers Union.

Whole Foods workers in a Pennsylvania store vote to form the first union under Amazon ownership, joining a local chapter of the UFCW.

The union win, at a Philadelphia store where workers are seeking higher wages, comes as Amazon is also fighting organizing efforts among some warehouse employees and delivery drivers.