Cash App complaint: Bitcoin seized for review

I was requested to pay for an item by sending $400 in BTC to a cash app users BTC wallet. Cash App would not sellme the Bitcoin through their app so I sent them from an external wallet. The BTC was immediately seized and being held for review. That was 5 hours ago. The seller wouldn’t give me the item because of it not being in his account and I can’t get my money back because Cash App has seized it. I have written to their support and Squares support and their response was that they will get back to me. I have been ripped off $400 dollars because I know I’ll never see the man again and the police couldn’t do anything about it. He wasn’t paid because Cash App has it in their possession, not the man who is selling the item. It was recommended to never use cash app again because it’s untrustworthy because they are known to do whatever they want and don’t have to answer to anyone for.it. I am livid over this. Cash App is a horrible monster!