A group of Toronto delivery drivers say Amazon is blocking their attempts to unionize about 770 workers, and they’re asking the Ontario Labour Relations Board to order a new vote.

The drivers, represented by the United Food and Commercial Workers Canada (UFCW), Local 175, allege that Amazon Canada Fulfillment Services is subjecting them to unfair labour practices and has violated the Ontario Labour Relations Act (OLRA) by blocking their efforts to unionize.

“We were approached by delivery drivers who expressed they had concerns about their working conditions and were seeking the aid of a trade union—in this case us—to unionize them in order to deal with their employer,” Tim Deelstra, a spokesperson for UFCW, which filed the complaint on July 20, told The Logic.