The only real fix is actual accountability for lawmakers. It means massive amounts of oversight to catch those who accept bribes in any forms (including "campaign contributions") and it means making it simple for the people to vote out anyone who refuses to represent their interests.

Right now, bribery is effectively legal, there is zero accountability and between the two party system, gerrymandering, and voter suppression even if you manage to get someone out of office you're probably not going to like the person you're forced to vote in to replace them. We're a very long way from fixing the problem and all of the people in power have zero incentive to start getting us there because they profit off the system being broken.

Honestly though, actually reaching out to your representatives and talking to them is far more effective than most people assume.