fair complaint about Audiogon, violating no guidelines, removed

+1, cleeds.
I had suggested OP in his original thread to invite the seller for an open discussion. I understand OP’s frustration, he was probably treated unfairly. Without hearing seller’s side of story, we are unlikely to resolve anything or reach amicable solution.

Without rules, all there is chaos.

This site is so highly censored.  There are so many other audio forums out there...

I am not looking for solution with seller, he gave me back my money.  I am looking for Audiogon to not permit sellers to break contracts, such as this seller did. Additionally, they should permit me to put appropriate feedback, which they did NOT

Because we can't see what you wrote its hard to tell.  But in general the moderators seem to have set out clear do's and don'ts and have stuck to them.

I am looking for Audiogon to not permit sellers to break contracts

That is probably asking too much of an entity that provides a platform to facilitate buying and selling of used stuff. Contract disputes are handled by our legal system. The best you could probably hope for is for Audiogon to ban bad actors but there are two sides to every story and banning folks is a serious business and a slippery slope. Audiogon does encourage good behavior and discourage bad behavior through their feedback system. I have certainly gone the extra mile on transactions to maintain good feedback and I know others here do that too. Back in the day, they used to post some disputes and let members weigh in....that was sort of fun unless you were one of the folks in the dispute.