I’m sorry to hear about your situation. Brave doesn’t have live support, so if someone claimed to be Brave support, it’s likely they were a scammer.
There’s a pinned warning about this at NOTICE: Brave will NEVER ask for your private Wallet data/keys
I shared an image there that might be helpful:
It sounds like the scammer may have accessed your wallet. The warning in the template advises against sharing sensitive information:
Unfortunately, if someone obtained your seed phrases or private keys, there’s not much that can be done to recover the assets. This is why it’s crucial to never share your seed phrases or private keys with anyone. Once assets are gone, they’re generally gone forever, especially with self-custody wallets.