I know of a racer that is constantly changing their weight to a lower-than-reality number. I have reported them to zwift, who claims they have intervened, but the weight has dropped back down again. What other course of action is there?
Oh and they place well in races that they might otherwise not.
Report them again to Zwift Support with any and all screenshots and documentation you have.
How do I prove they are bigger than they claim to be?
If you know they are changing their weight on Zwift you should get a screenshot of before and after they adjust it. The difference is going have to be more than a few pounds though to raise eyebrows.
If they are on Zwift power you can see the weight for every race.
it’s already set to the lower weight right now
Did you ever think that they are actually the lower weight and raise it to a higher weight for training purposes? I trained IRL with my heaviest wheel set and put on my lighter wheels for group rides.