Mercari received broken item, they refused to refund

I bought an item on Mercari. It arrived broken so I contacted them to report that and the fact that I could not access my account. I was told, by the first person in this event, that someone would contact me to request pictures and other info.

I waited for an email that never came so I contacted them again. Got a different person this time that said it sounded like this needed looking into and they would get back to me. Several days later I get an email saying they are sorry that can't help me, the seller has already been paid and the case is closed and I should have gotten ahold of them sooner.

I did get ahold of them, they dropped the ball and now they refuse to do anything. They said it is their policy that if the buyer has not left feedback for the seller within 3 days, they automatically give them a 5 star rating, pay them and the sale is closed.

No refunds will be paid after the seller is paid. So even though there was an open issue and I was waiting on them to tell me what I needed to do, they finalized the sale and basically told me too bad, we can't help you. 

It says right on their main page, money back guarantee if you item is not as described. Well my item was not described as broken and now I guess I am just out the money I spent.

I would not recommend Mercari to anyone because there is no guarantee you will get what you paid for and you sure won't get a refund.