lobby against (someone or something)
To try to influence someone, especially an elected official or group of elected officials, against someone or something. A number of high-profile corporations have been lobbying against the supreme court nominee. We've been lobbying against legislation aimed at tightening voter access for the last half a century.
lobby against something
to solicit support against something, such as a piece of legislation or a government regulation. We sent a lot of lawyers to the state capital to lobby against the bill, but it passed anyway. They lobbied against the tax increase.