Patty Greiner lost $15,000 after receiving a text claiming her Amazon account was hacked. "There's been multiple purchases and your account has been flagged for fraudulent activity," Greiner said she was told. She said she was contacted by individuals posing as IRS agents and federal law enforcement, who threatened her with arrest if she did not comply. "They talked like they were very intelligent; they knew the system," Greiner said. Scammers aren't just impersonating law enforcement and federal officials; they're now stepping up their game to clone voices to drain victims' bank accounts. Leanne Lanigan, from the Better Business Bureau…