Lost $6,800 USDT Through Fake Exchange App, Partial Refund Given

I was scammed by an international call claiming to be from a trading exchange app. They demanded payments for taxes, insurance, and other fees, leading to a total loss of $17,800 in USDT. After realizing it was a scam, I contacted "usdtfinans" on Telegram, who investigated the issue and froze the scammer’s account. However, there was only $11,000 USDT left in the account, which they refunded to me. I am still at a loss for the remaining $6,800 USDT and have no idea how to recover it. This is devastating, and I demand further action to retrieve the rest of my funds. If anyone has advice or if Tether can assist, please help resolve this!