Violation of federal antitrust laws requires proof that an organization is actively seeking to monopolize an industry not on its own merit, but with the intents to control the market through unfair practices. There's a lot of ambiguity in the law, which typically means that the U.S. Department of Justice, or a state attorney general is required to bring charges to protect the public interests.
In your circumstance, I believe that the issue would boil down to whether or not you and others like you have other options in the same market space. If yes, then there's likely no antitrust violation. Otherwise, there may be an unlawful monopoly.
That said, the best thing to do is complain to the government and try to get some media attention, as well. If enough people complain, and enough media attention is focused on the issue, the government investigates (and, sometimes, the offending organization reverses course voluntarily).
That's how I would handle the issue, based upon your stated facts.
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